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 Chin. Phys. B
 Chin. Phys. B--2010, Vol.19, No.5
GENERAL
Xie Shui-Ying, Lin Ji
Chin. Phys. B 2010, 19 (5): 050201;  doi: 10.1088/1674-1056/19/5/050201
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We investigate the one-dimensional nonlinear Schr\"{o}dinger equation with a perturbation of polynomial type. The approximate symmetries and approximate symmetry reduction equations are obtained with the approximate symmetry perturbation theory.
Wang You-Fa, Lou Sen-Yue, Qian Xian-Min
Chin. Phys. B 2010, 19 (5): 050202;  doi: 10.1088/1674-1056/19/5/050202
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According to the conjecture based on some known facts of integrable models, a new (2+1)-dimensional supersymmetric integrable bilinear system is proposed. The model is not only the extension of the known (2+1)-dimensional negative Kadomtsev--Petviashvili equation but also the extension of the known (1+1)-dimensional supersymmetric Boussinesq equation. The infinite dimensional Kac--Moody--Virasoro symmetries and the related symmetry reductions of the model are obtained. Furthermore, the traveling wave solutions including soliton solutions are explicitly presented.
Shi Lan-Fang, Mo Jia-Qi
Chin. Phys. B 2010, 19 (5): 050203;  doi: 10.1088/1674-1056/19/5/050203
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This paper considers a class of boundary value problems for the semilinear singularly perturbed fractional differential equation. Under the suitable conditions, firstly, the outer solution of the original problem is obtained; secondly, using the stretched variable and the composing expansion method the boundary layer is constructed; finally, using the theory of differential inequalities the asymptotic behaviour of solution for the problem is studied and the uniformly valid asymptotic estimation is discussed.
Ruan Hang-Yu
Chin. Phys. B 2010, 19 (5): 050204;  doi: 10.1088/1674-1056/19/5/050204
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Through analysing the exact solution of some nonlinear models, the role of the variable separating method in solving nonlinear equations is discussed. We find that rich solution structures of some special fields of these equations come from the nonzero seed solution. However, these nonzero seed solutions is likely to result in the divergent phenomena for the other field component of the same equation. The convergence and the signification of all field components should be discussed when someone solves the nonlinear equation using the variable separating method.
Chen Han-Shuang, Hou Zhong-Huai, Zhang Ji-Qian, Xin Hou-Wen
Chin. Phys. B 2010, 19 (5): 050205;  doi: 10.1088/1674-1056/19/5/050205
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We study evolutionary prisoner's dilemma game on adaptive networks where a population of players co-evolves with their interaction networks. During the co-evolution process, interacted players with opposite strategies either rewire the link between them with probability $p$ or update their strategies with probability $1-p$ depending on their payoffs. Numerical simulation shows that the final network is either split into some disconnected communities whose players share the same strategy within each community or forms a single connected network in which all nodes are in the same strategy. Interestingly, the density of cooperators in the final state can be maximised in an intermediate range of $p$ via the competition between time scale of the network dynamics and that of the node dynamics. Finally, the mean-field analysis helps to understand the results of numerical simulation. Our results may provide some insight into understanding the emergence of cooperation in the real situation where the individuals' behaviour and their relationship adaptively co-evolve.
Mei Feng-Xiang, Wu Hui-Bin
Chin. Phys. B 2010, 19 (5): 050301;  doi: 10.1088/1674-1056/19/5/050301
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A form invariance and a conserved quantity of the generalised Birkhoffian system are studied. Firstly, a definition and a criterion of the form invariance are given. Secondly, through the form invariance, a new conserved quantity can be deduced. Finally, an example is given to illustrate the application of the result.
Chen Tao, Huang Yan-Xia, Shan Chuan-Jia, Li Jin-Xing, Liu Ji-Bing, Liu Tang-Kun
Chin. Phys. B 2010, 19 (5): 050302;  doi: 10.1088/1674-1056/19/5/050302
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This paper investigates the entanglement evolution of a two-qubit anisotropic Heisenberg XYZ chain in the presence of Dzyaloshinskii--Moriya interaction. The time evolution of the concurrence is studied for the initial pure entangled states $\cos \theta \left\vert 00\right\rangle +\sin \theta \left\vert 11\right\rangle$ and $\cos \phi \left\vert 01\right\rangle +\sin \phi \left\vert 10\right\rangle$ at zero temperature. The influences of Dzyaloshinskii--Moriya interaction $D$, anisotropic parameter $\varDelta$ and environment coupling strength $\gamma$ on entanglement evolution are analysed in detail. It is found that the effect of noisy environment obviously suppresses the entanglement evolution, and the Dzyaloshinskii--Moriya interaction $D$ acts on the time evolution of entanglement only when the initial state is $\cos \phi \left\vert 01\right\rangle +\sin \phi \left\vert 10\right\rangle$. Finally, a formula of steady state concurrence is obtained, and it is shown that the stable concurrence, which is independent of different initial states and Dzyaloshinskii--Moriya interaction $D$, depends on the anisotropic parameter $\varDelta$ and the environment coupling strength $\gamma$.
Fan Hong-Yi
Chin. Phys. B 2010, 19 (5): 050303;  doi: 10.1088/1674-1056/19/5/050303
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By introducing the $s$-parameterized generalized Wigner operator into phase-space quantum mechanics we invent the technique of integration within $s$-ordered product of operators (which considers normally ordered, antinormally ordered and Weyl ordered product of operators as its special cases). The $s$-ordered operator expansion (denoted by $\circledS \cdots \circledS)$ formula of density operators is derived, which is $$\rho=\frac{2}{1-s}\int \frac{\d^2\beta}{\pi}\left \langle -\beta \right \vert \rho \left \vert \beta \right \rangle \circledS \exp \Big\{ \frac{2}{s-1}\left( s|\beta|^{2}-\beta^{\ast}a+\beta a^{\dagger}-a^{\dagger}a\right) \Big\} \circledS.$$ The $s$-parameterized quantization scheme is thus completely established.
Chen Shi-Rong, Xia Yun-Jie, Man Zhong-Xiao
Chin. Phys. B 2010, 19 (5): 050304;  doi: 10.1088/1674-1056/19/5/050304
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In this paper, we study the quantum phase transition and the effect of impurity on the thermal entanglement between any two lattices in three-qubit Heisenberg XX chain in a uniform magnetic field. We show that the quantum phase transition always appears when impurity parameter is an arbitrary constant and unequal to zero, the external magnetic field and impurity parameters have a great effect on it. Also, there exists a relation between the quantum phase transition and the entanglement. By modulating the temperature, magnetic field and the impurity parameters, the entanglement between any two lattices can exhibit platform-like behaviour, which can be used to realize entanglement switch.
Hu Xue-Yuan, Gu Ying, Gong Qi-Huang, Guo Guang-Can
Chin. Phys. B 2010, 19 (5): 050305;  doi: 10.1088/1674-1056/19/5/050305
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We demonstrate that the $n$-partite continuous-variable entanglement can be unconditionally prepared among $n$ parties that share no common past, from $n$ two-mode squeezed states. Both GHZ-like and cluster-like states can be generated for any nonzero squeezing in the entangled sources. An application of the resulting multipartite entangled state to a teleportation network is illustrated.
Yang Yu-Guang, Cao Wei-Feng, Wen Qiao-Yan
Chin. Phys. B 2010, 19 (5): 050306;  doi: 10.1088/1674-1056/19/5/050306
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Based on $\chi$-type entangled states and the two-step protocol [Deng F G, Long G L and Liu X S 2003 {\it Phys. Rev.} A {\bf68} 042317], a quantum secret sharing protocol of secure direct communication based on $\chi$-type entangled states $\vert \chi ^{00}\rangle _{3214}$ is proposed. Using some interesting entanglement properties of this state, the agent entirety can directly obtain the secret message from the message sender only if they collaborate together. The security of the scheme is also discussed.
I. I. Guseinov, B. A. Mamedov
Chin. Phys. B 2010, 19 (5): 050501;  doi: 10.1088/1674-1056/19/5/050501
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A new analytical approach to the computation of the Fermi-Dirac (FD) functions is presented, which was suggested by previous experience with various algorithms. Using the binomial expansion theorem, these functions are expressed through the binomial coefficients and familiar incomplete Gamma functions. This simplification and the use of the memory of the computer for calculation of binomial coefficients may extend the limits to large arguments for users and result in speedier calculation, should such limits be required in practice. Some numerical results are presented for significant mapping examples and they are briefly discussed.
Wang Jian-Hui, Ma Yong-Li
Chin. Phys. B 2010, 19 (5): 050502;  doi: 10.1088/1674-1056/19/5/050502
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We have investigated the thermodynamic behaviour of ideal Bose gases with an arbitrary number of particles confined in a harmonic potential. By taking into account the conservation of total number $N$ of particles and using a saddle-point approximation, we derive analytically the simple explicit expression of mean occupation number in any state of the finite system. The temperature dependence of the chemical potential, specific heat, and condensate fraction for the trapped finite-size Bose system is obtained numerically. We compare our results with the usual treatment which is based on the grand canonical ensemble. It is shown that there exists a considerable difference between them at sufficiently low temperatures, specially for the relative small numbers of Bose atoms. The finite-size scaling at the transition temperature for the harmonically trapped systems is also discussed. We find that the scaled condensate fractions for various system sizes and temperatures collapse onto a single scaled form.
Song Pei-Jun, Lü Xin-You, Liu Ji-Bing, Hao Xiang-Ying
Chin. Phys. B 2010, 19 (5): 050503;  doi: 10.1088/1674-1056/19/5/050503
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By using a two-mode mean-field approximation, we study the dynamics of the microcavities containing semiconductor quantum wells. The exact analytical solutions are obtained in this study. Based on these solutions, we show that the emission from the microcavity manifests periodic oscillation behaviour and the oscillation can be suppressed under a certain condition.
Yang Jian-Hua, Liu Xian-Bin
Chin. Phys. B 2010, 19 (5): 050504;  doi: 10.1088/1674-1056/19/5/050504
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The phenomenon of stochastic resonance is investigated in an asymmetric bistable system with coloured noises. The approximate Fokker--Planck equation is derived based on the Novikov theorem and the Fox approach. By applying the two-state theory, the expression of the signal-to-noise ratio is obtained in the adiabatic limit. The effects of the noise parameters on signal-to-ratio are discussed. It is found that the stochastic resonance phenomena appear in most cases and disappear in some special cases.
Wei Heng-Dong, Li Li-Ping, Guo Jian-Xiu
Chin. Phys. B 2010, 19 (5): 050505;  doi: 10.1088/1674-1056/19/5/050505
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It is an important problem in chaos theory whether an observed irregular signal is deterministic chaotic or stochastic. We propose an efficient method for distinguishing deterministic chaotic from stochastic time series for short scalar time series. We first investigate, with the increase of the embedding dimension, the changing trend of the distance between two points which stay close in phase space. And then, we obtain the differences between Gaussian white noise and deterministic chaotic time series underlying this method. Finally, numerical experiments are presented to testify the validity and robustness of the method. Simulation results indicate that our method can distinguish deterministic chaotic from stochastic time series effectively even when the data are short and contaminated.
Ma Da-Zhong, Zhang Hua-Guang, WangZhan-Shan, Feng Jian
Chin. Phys. B 2010, 19 (5): 050506;  doi: 10.1088/1674-1056/19/5/050506
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In this paper the fault tolerant synchronization of two chaotic systems based on fuzzy model and sample data is investigated. The problem of fault tolerant synchronization is formulated to study the global asymptotical stability of the error system with the fuzzy sampled-data controller which contains a state feedback controller and a fault compensator. The synchronization can be achieved no matter whether the fault occurs or not. To investigate the stability of the error system and facilitate the design of the fuzzy sampled-data controller, a Takagi--Sugeno (T--S) fuzzy model is employed to represent the chaotic system dynamics. To acquire the good performance and produce less conservative analysis result, a new parameter-dependent Lyapunov--Krasovksii functional and a relaxed stabilization technique are considered. The stability conditions based on linear matrix inequality are obtained to achieve the fault tolerant synchronization of the chaotic systems. Finally, a numerical simulation is shown to verify the results.
S. M. Lee, O. M. Kwon, Ju H. Park
Chin. Phys. B 2010, 19 (5): 050507;  doi: 10.1088/1674-1056/19/5/050507
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In this paper, new delay-dependent stability criteria for asymptotic stability of neural networks with time-varying delays are derived. The stability conditions are represented in terms of linear matrix inequalities (LMIs) by constructing new Lyapunov--Krasovskii functional. The proposed functional has an augmented quadratic form with states as well as the nonlinear function to consider the sector and the slope constraints. The less conservativeness of the proposed stability criteria can be guaranteed by using convex properties of the nonlinear function which satisfies the sector and slope bound. Numerical examples are presented to show the effectiveness of the proposed method.
Li Heng-Jian, Zhang Jia-Shu
Chin. Phys. B 2010, 19 (5): 050508;  doi: 10.1088/1674-1056/19/5/050508
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In this study an adaptive arithmetic coder is embedded in the Baptista-type chaotic cryptosystem for implementing secure data compression. To build the multiple lookup tables of secure data compression, the phase space of chaos map with a uniform distribution in the search mode is divided non-uniformly according to the dynamic probability estimation of plaintext symbols. As a result, more probable symbols are selected according to the local statistical characters of plaintext and the required number of iterations is small since the more probable symbols have a higher chance to be visited by the chaotic search trajectory. By exploiting non-uniformity in the probabilities under which a number of iteration to be coded takes on its possible values, the compression capability is achieved by adaptive arithmetic code. Therefore, the system offers both compression and security. Compared with original arithmetic coding, simulation results on Calgary Corpus files show that the proposed scheme suffers from a reduction in compression performance less than 12{\%} and is not susceptible to previously carried out attacks on arithmetic coding algorithms.
Zhou Guo-Hua, Bao Bo-Cheng, Xu Jian-Ping, Jin Yan-Yan
Chin. Phys. B 2010, 19 (5): 050509;  doi: 10.1088/1674-1056/19/5/050509
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The dynamical behaviours of valley current controlled buck converter are studied by establishing its corresponding discrete iterative map model in this paper. Time-domain waveforms and phase portraits of valley current controlled buck converter are obtained by Runge--Kutta algorithm through a piecewise smooth switching model. The research results indicate that the valley current controlled buck converter exhibits rich nonlinear phenomena, and it has routes to chaos through period-doubling bifurcation and border-collision bifurcation in a wide parameter range. Interesting inverse nonlinear behaviours compared with peak current controlled buck converter are observed in the valley current controlled buck converter. Analysis and simulation results are verified by experimental results.
Xie Zong-Bo, FengJiu-Chao
Chin. Phys. B 2010, 19 (5): 050510;  doi: 10.1088/1674-1056/19/5/050510
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The denoising problem of impure chaotic signals is addressed in this paper. A method based on sparse representation is proposed, in which the random frame dictionary is generated by a chaotic random search algorithm. The numerical simulation shows the proposed algorithm outperforms those recently reported alternative denoising methods.
Qin Ying-Hua, Luo Xiao-Shu, WeiDu-Qu
Chin. Phys. B 2010, 19 (5): 050511;  doi: 10.1088/1674-1056/19/5/050511
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This paper studies how random phase (namely, noise-perturbed phase) effects the dynamical behaviours of a simple model of power system which operates in a stable regime far away from chaotic behaviour in the absence of noise. It finds that when the phase perturbation is weak, chaos is absent in power systems. With the increase of disturbed intensity $\sigma$, power systems become unstable and fall into chaos as $\sigma$ further increases. These phenomena imply that random phase can induce and enhance chaos in power systems. Furthermore, the possible mechanism behind the action of random phase is addressed.
Zhang Yong-Ping, Sun Wei-Hua, Liu Chang-An
Chin. Phys. B 2010, 19 (5): 050512;  doi: 10.1088/1674-1056/19/5/050512
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A visualization of Julia sets of the complex Henon map system with two complex variables is introduced in this paper. With this method, the optimal control function method is introduced to this system and the control and synchronization of its Julia sets are achieved. Control and synchronization of generalized Julia sets are also achieved with this optimal control method. The simulations illustrate the efficacy of this method.
Qian Yu, Huang Xiao-Dong, Liao Xu-Hong, Hu Gang
Chin. Phys. B 2010, 19 (5): 050513;  doi: 10.1088/1674-1056/19/5/050513
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This paper investigates antispiral wave breakup phenomena in coupled two-dimensional FitzHugh--Nagumo cells with self-sustained oscillation via Hopf bifurcation. When the coupling strength of the active variable decreases to a critical value, wave breakup phenomenon first occurs in the antispiral core region where waves collide with each other and spontaneously break into spatiotemporal turbulence. Measurements reveal for the first time that this breakup phenomenon is due to the mechanism of antispiral Doppler instability.
Gan Zheng-Ning, Cheng Xin-Ming
Chin. Phys. B 2010, 19 (5): 050514;  doi: 10.1088/1674-1056/19/5/050514
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In this paper, we propose the distributed predictive control strategies of spiral wave in cardiac excitable media. The modified FitzHugh--Nagumo model was used to express the cardiac excitable media approximately. Based on the control-Lyapunov theory, we obtained the distributed control equation, which consists of a positive control-Lyapunov function and a positive cost function. Using the equation, we investigate two kinds of robust control strategies: the time-dependent distributed control strategy and the space-time dependent distributed control strategy. The feasibility of the strategies was demonstrated via an illustrative example, in which the spiral wave was prevented to occur, and the possibility for inducing ventricular fibrillation was eliminated. The strategies are helpful in designing various cardiac devices. Since the second strategy is more efficient and robust than the first one, and the response time in the second strategy is far less than that in the first one, the former is suitable for the quick-response control systems. In addition, our spatiotemporal control strategies, especially the second strategy, can be applied to other cardiac models, even to other reaction-diffusion systems.
Gu Guo-Feng, L\"u Yao-Ping, Tang Guo-Ning
Chin. Phys. B 2010, 19 (5): 050515;  doi: 10.1088/1674-1056/19/5/050515
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This paper uses the two-dimensional Brusselator model to study reflection and refraction of chemical waves. It presents some boundary conditions of chemical waves, with which occurence of observed phenomena at interface as refraction and reflection of chemical waves can be interpreted. Moreover, the angle of reflection may be calculated by using the boundary conditions. It finds that reflection and refraction of chemical waves can occur simultaneously even if plane wave goes from a medium with higher speed to a medium with lower speed, provided the incident angle is larger than the critical angle.
Li Hai-Hong, Xiao Jing-Hua, Hu Gang, HuBambi
Chin. Phys. B 2010, 19 (5): 050516;  doi: 10.1088/1674-1056/19/5/050516
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Dynamical behaviour of the one-dimensional complex Ginzburg--Landau equation (CGLE) with finite system size $L$ is investigated, based on numerical simulations. By varying the system size and keeping other system parameters in the defect turbulence region (defect turbulence in large $L$ limit), a number of intermittencies new for the CGLE system are observed in the processes of pattern formations and transitions while the system dynamics varies from a homogeneous periodic oscillation to strong defect turbulence.
Tang Tie-Qiao, Huang Hai-Jun, Shang Hua-Yan
Chin. Phys. B 2010, 19 (5): 050517;  doi: 10.1088/1674-1056/19/5/050517
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Since ramp is an important composition of traffic system and there often exist multi ramps in a traffic system, the number of ramps can have great effects on main road traffic and produce some complex phenomena. In this paper, we employ the model presented by Tang \textit{et al}. [2009 {\em Communications in Theoretical Physics} {\bf 51}({1}) 71] to further study the effects of the number of on-ramps on the stability of traffic flow on a ring road. The numerical results show that this model can reproduce some complex traffic phenomena resulting from multi on-ramps on the ring road and the effects of the number of on-ramps on traffic flow, but the phenomena and the effects are both related to the initial density of the main road.
Bayram Deviren, Osman Canko, Mustafa Keskin
Chin. Phys. B 2010, 19 (5): 050518;  doi: 10.1088/1674-1056/19/5/050518
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Recently, Shi {\it et al.} [2008 {\it Phys. Lett.} A {\bf372} 5922] have studied the dynamical response of the kinetic Ising model in the presence of a sinusoidal oscillating field and presented the dynamic phase diagrams by using an effective-field theory (EFT) and a mean-field theory (MFT). The MFT results are in conflict with those of earlier work of Tom\'{e} and de Oliveira, [1990 {\it Phys. Rev.} A {\bf41} 4251]. We calculate the dynamic phase diagrams and find that our results are similar to those of earlier work of Tom\'{e} and de Oliveira; hence the dynamic phase diagrams calculated by Shi {\it et al.} are incomplete within both theories, except the low values of frequencies for the MFT calculation. We also investigate the influence of external field frequency ($\omega$) and static external field amplitude ($h_{0})$ for both MFT and EFT calculations. We find that the behaviour of the system strongly depends on values of $\omega$ and $h_{0}$.
Ou-Yang Shi-Hua, Lam Chi-Hang, You Jian-Qiang
Chin. Phys. B 2010, 19 (5): 050519;  doi: 10.1088/1674-1056/19/5/050519
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We study shot noise in tunneling current through a double quantum dot connected to two electric leads. We derive two master equations in the occupation-state basis and the eigenstate basis to describe the electron dynamics. The approach based on the occupation-state basis, despite being widely used in many previous studies, is valid only when the interdot coupling strength is much smaller than the energy difference between the two dots. In contrast, the calculations using the eigenstate basis are valid for an arbitrary interdot coupling. Using realistic model parameters, we demonstrate that the predicted currents and shot-noise properties from the two approaches are significantly different when the interdot coupling is not small. Furthermore, properties of the shot noise predicted using the eigenstate basis successfully reproduce qualitative features found in a recent experiment.
Gao Li-Xin, Yan Hui-Juan, Jin Dan
Chin. Phys. B 2010, 19 (5): 050520;  doi: 10.1088/1674-1056/19/5/050520
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In this paper, we consider multi-agent consensus problems in a decentralised fashion. The interconnection topology graph among the agents is switching and undirected. The agent dynamics is expressed in the form of a double integrator model. Two different cases are considered in this study. One is the leader-following case and the other is leaderless case. Based on graph theory and common Lyapunov function method, some sufficient conditions are obtained for the consensus stability of the considered systems with the neighbour-based feedback laws in both leader-following case and leaderless case respectively. Finally, two numerical examples are given to illustrate the obtained results.
Li Yuan, Qian Jian-Qiang, Li Ying-Zi
Chin. Phys. B 2010, 19 (5): 050701;  doi: 10.1088/1674-1056/19/5/050701
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The periodic impact force induced by tip-sample contact in tapping mode atomic force microscope (AFM) gives rise to non-harmonic response of a micro-cantilever. These non-harmonic signals contain the full characteristics of tip-sample interaction. A complete theoretical model describing the dynamical behaviour of tip--sample system was developed in this paper. An analytic formula was introduced to describe the relationship between time-varying tip--sample impact force and tip motion. The theoretical analysis and numerical results both show that the time-varying tip--sample impact force can be reconstructed by recording tip motion. This allows for the reconstruction of the characteristics of the tip--sample force, like contact time and maximum contact force. It can also explain the ability of AFM higher harmonics imaging in mapping stiffness and surface energy variations.
ATOMIC AND MOLECULAR PHYSICS
Shen Xiao-Zhi, Yuan Ping, Liu Juan
Chin. Phys. B 2010, 19 (5): 053101;  doi: 10.1088/1674-1056/19/5/053101
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By applying systematically enlarged multi-configuration Dirac--Fock wavefunction, the transitions for electric-dipole allowed (E1) and forbidden (E2, M1 and M2) lines are studied among 4f pair coupling and low-lying configurations for singly ionized nitrogen. Most important effects of relativity, electron correlation, the rearrangement of electron density, Breit interaction, and quantum electrodynamic effects are included in the computation. Then, allowed (E1) and forbidden (E2, M1 and M2) transition probabilities of 4f for N$^{+}$ are obtained and compared with experimental results. Good agreement with available experimental results is found and most of data of 4f are presented for the first time.
Zhang Xiao-Niu, Shi De-Heng, Zhang Jin-Ping, Zhu Zun-Lüe, Sun Jin-Feng
Chin. Phys. B 2010, 19 (5): 053401;  doi: 10.1088/1674-1056/19/5/053401
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Equilibrium internuclear separations, harmonic frequencies and potential energy curves (PECs) of HCl($X^{1}\Sigma ^{ + })$ molecule are investigated by using the highly accurate valence internally contracted multireference configuration interaction (MRCI) approach in combination with a series of correlation-consistent basis sets in the valence range. The PECs are all fitted to the Murrell--Sorbie function, and they are used to accurately derive the spectroscopic parameters ($D_{\rm e}$, $D_{0}$, $\omega_{\rm e}\chi_{\rm e}$, $\alpha_{\rm e}$ and $B_{\rm e})$. Compared with the available measurements, the PEC obtained at the basis set, aug-cc-pV5Z, is selected to investigate the vibrational manifolds. The constants $D_{0}$, $D_{\rm e}$, $R_{\rm e}$, $\omega_{\rm e}$, $\omega_{\rm e}\chi_{\rm e}$, $\alpha_{\rm e}$ and $B_{\rm e}$ at this basis set are 4.4006~eV, 4.5845~eV, 0.12757~nm, 2993.33~cm$^{ - 1}$, 52.6273~cm$^{ - 1}$, 0.2981~cm$^{ - 1}$ and 10.5841~cm$^{ - 1}$, respectively, which almost perfectly conform to the available experimental results. With the potential determined at the MRCI/aug-cc-pV5Z level of theory, by numerically solving the radial Schr\"{o}dinger equation of nuclear motion in the adiabatic approximation, a total of 21 vibrational levels are predicted. Complete vibrational levels, classical turning points, inertial rotation and centrifugal distortion constants are reproduced, which are in excellent agreement with the available Rydberg--Klein--Rees data. Most of these theoretical vibrational manifolds are reported for the first time to the best of our knowledge.
Chen De-Ying, Zhang Hong-Ying, Fan Rong-Wei
Chin. Phys. B 2010, 19 (5): 053402;  doi: 10.1088/1674-1056/19/5/053402
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The four-level model of laser-induced collisional energy transfer (LICET) for ion--ion collision system is established based on the time-dependent Schr\"{o}dinger equation for the electron dynamics, through which the equations of motion of the probability amplitudes and cross section of the collision system are obtained. Numerical calculations are performed for the Ca$^+$--Sr$^+$ system, with the results showing that the peak of the LICET spectrum appears at a resonant frequency of the transfer laser. The magnitude of the obtained collision cross section is in the order of $10^{-16}$~cm$^2$, and is comparable to that obtained in atomic systems, which indicates the validity of the established four-level model.
CLASSICAL AREAS OF PHENOMENOLOGY
Yang Chao, Guo Li-Xin, Wu Zhen-Sen
Chin. Phys. B 2010, 19 (5): 054101;  doi: 10.1088/1674-1056/19/5/054101
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This paper is devoted to the study of polarization properties, scattering properties and propagation properties of global positioning system (GPS) scattering signal over the rough sea surface. To investigate the polarization and the scattering properties, the scattering field and the bistatic scattering coefficient of modified Kirchhoff approximation with using the tapered incident wave is derived in detail. In modeling the propagation properties of the GPS scattering signal in the evaporation duct, the initial field of parabolic equation traditionally computed by the antenna pattern with using fast Fourier transform (FFT) is replaced by the GPS scattering field. And the propagation properties of GPS scattering signal in the evaporation duct with different evaporation duct heights and elevation angles of GPS are discussed by the improved discrete mixed Fourier transform with taking into account the sea surface roughness.
Xie Tao, Shen Tao, William Perrie, Chen Wei, Kuang Hai-Lan
Chin. Phys. B 2010, 19 (5): 054102;  doi: 10.1088/1674-1056/19/5/054102
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To study the electromagnetic (EM) backscatter characteristics of freak waves at moderate incidence angles, we establish an EM backscattering model for freak waves in (1+1)-dimensional deep water. The nonlinear interaction between freak waves and Bragg short waves is considered to be the basic hydrodynamic spectra modulation mechanism in the model. Numerical results suggest that the EM backscattering intensities of freak waves are less than those from the background sea surface at moderate incidence angles. The normalised radar cross sections (NRCSs) from freak waves are highly polarisation dependent, even at low incidence angles, which is different from the situation for normal sea waves; moreover, the NRCS of freak waves is more polarisation dependent than the background sea surface. NRCS discrepancies between freak waves and the background sea surface with using horizontal transmitting horizomtal (HH) polarisation are larger than those with using vertical transmitting vertical (VV) polarisation, at moderate incident angles. NRCS discrepancies between freak waves and background sea surface decreases with the increase of incidence angle, in both HH and VV polarisation radars. As an application, in the synthetic-aperture radar (SAR) imaging of freak waves, we suggest that freak waves should have extremely low backscatter NRCSs for the freak wave facet with the strongest slope. Compared with the background sea surface, the freak waves should be darker in HH polarisation echo images than in VV echo images, in SAR images. Freak waves can be more easily detected from the background sea surface in HH polarisation images than in VV polarisation images. The possibility of detection of freak waves at low incidence angles is much higher than at high incidence angles.
Zhang Yan-Min, Wang Yun-Hua, Guo Li-Xin
Chin. Phys. B 2010, 19 (5): 054103;  doi: 10.1088/1674-1056/19/5/054103
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Backscattered fields from one-dimensional time-varying Gerstners sea surface are calculated utilising the second-order small slope approximation. It is well known that spectral properties of the backscattered echoes relate to the velocity of the small elementary scatterers on sea surface profiles. Therefore, modeling Doppler spectra from the ocean requires an accurate description of the sea surface motion. The profile of nonlinear Gerstners sea surface shows vertical-skewness of sea waves, it is sharper at the crest and flatter at the trough than linear waves, and its maximum slope position is closer to the crest than to the trough. Furthermore, the horizontal component of the small elementary scatterers orbit velocity on the sea surface, which yields noticeable influence on Doppler spectra, can be obtained conveniently by Gerstners sea surface model. In this study, the characteristics of Doppler spectra of backscattered fields from time-varying Gerstners sea surface are investigated and the dependences of the Doppler frequency and the Doppler bandwidth on the parameters, such as the wind speed, the radar frequency, the incident angle, etc. are discussed. It is shown that the Doppler bandwidth of microwave scattered fields from Gerstners sea surface is considerably broadened. For the case of high frequency backscattered fields, the values of the higher-order spectrum peaks are larger than those obtained by linear sea surface.
Liu Jian-Long, Lin Jie, Zhao Hai-Fa, Zhang Yan, Liu Shu-Tian
Chin. Phys. B 2010, 19 (5): 054201;  doi: 10.1088/1674-1056/19/5/054201
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The enhancement characteristics of the local field in the surface plasmon nanocavities are investigated numerically. The cavity is constructed by placing a defect structure in the thickness-modulated metal--insulator--metal waveguide Bragg gratings. The characteristic impedance based transfer matrix method is used to calculate the transmission spectra and the resonant wavelength of the cavities with various geometric parameters. The finite-difference time-domain method is used to obtain the field pattern of the resonant mode and validate the results of the transfer matrix method. The calculation and simulation results reveal the existence of resonant wavelength shift and intensity variation with structural parameters, such as the modulation period of the gratings, the length and the width of the defect structure. Both numerical analysis and theoretical interpretation on these phenomena are given in details.
Wang Jian-Peng, Jin Yun-Xia, MaJian-Yong, Shao Jian-Da, Fan Zheng-Xiu
Chin. Phys. B 2010, 19 (5): 054202;  doi: 10.1088/1674-1056/19/5/054202
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Guided-mode resonance in a diffraction band of multilayer dielectric gratings may lead to a catastrophic result in laser system, especially in the ultrashort pulse laser system, so the inhibition of guided-mode resonance is very important. In this paper the characteristics of guided-mode resonance in multilayer dielectric grating are studied with the aim of better understanding the physical process of guided-mode resonance and designing a broadband multilayer dielectric grating with no guided-mode resonance. By employing waveguide theory, all guided-wave modes appearing in multilayer dielectric grating are found, and the incident conditions, separately, corresponding to each guided-wave mode are also obtained. The electric field enhancement in multilayer dielectric grating is shown obviously. Furthermore, from the detailed analyses on the guided-mode resonance conditions, it is found that the reduction of grating period would effectively avoid the appearing of guided-mode resonance. And the expressions for calculating maximum periods, which ensure that no guided-mode resonance occurs in the requiring broad angle or wavelength range, are first reported. The above results calculated by waveguide theory and Fourier mode method are compared wit each other, and they are coincident completely. Moreover, the method that relies on waveguide theory is more helpful for understanding the guided-mode resonance excited process and analyzing how each parameter affects the characteristic of guided-mode resonance. Therefore, the effects of multilayer dielectric grating parameters, such as period, fill factor, thickness of grating layer, {\it et al.}, on the guided-mode resonance characteristic are discussed in detail based on waveguide theory, and some meaningful results are obtained.
Li Jian-Long, Zhu Shi-Fu
Chin. Phys. B 2010, 19 (5): 054203;  doi: 10.1088/1674-1056/19/5/054203
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In this paper, the relation between spectral degree of coherence and degree of polarization of random electromagnetic beams is derived by the Stokes parameters. And the concept of polarization singularity is extended from spatially fully coherent beams to partially coherent electromagnetic beams. Theoretical analysis shows that correlation vortices are linearly polarized singularities. The results are illustrated by numerical examples.
Wang Yue-Yuan, Liu Zheng-Jun, Liao Qing-Hong, Liu Shu-Tian
Chin. Phys. B 2010, 19 (5): 054204;  doi: 10.1088/1674-1056/19/5/054204
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Phase properties of the even and odd circular states are studied within the Hermitian phase formalism of Pegg and Barnett. Exact analytical formulas for the distribution function and the variance of the phase operator are obtained and used to examine whether or not the even and odd circular states exhibit photon-number squeezing and phase squeezing.
Deng Li
Chin. Phys. B 2010, 19 (5): 054205;  doi: 10.1088/1674-1056/19/5/054205
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We numerically simulate three-photon absorption spectra in a three-coupled-quantum-well nanostructure interacting with a pump field, a coherent coupling field, and a probe field. We find that the three-photon absorption spectra can be dramatically influenced due to the intensities of the coupling field and pump field changing under the three-photon resonance condition. The effect of the frequency detuning of the pump field on the three-photon absorption spectra is also discussed. The study in our case is much more practical than the study in the case of its atomic counterpart in the sense of flexible design and the wide adjustable parameters. Thus it may open up some new possibilities for technological applications in optoelectronics and solid-state quantum information science.
Zhang Ke, Zhu Yan-Ping, Jiang Li, Zhang Han-Zhuang
Chin. Phys. B 2010, 19 (5): 054206;  doi: 10.1088/1674-1056/19/5/054206
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Through picture of dressed states, this paper investigates the spontaneous emission spectrum from a microwave-driven three-level atom embedded in a double-band photonic crystals. The physical dynamics of the phase dependent phenomenon is analysed by comparing two models upper level coupling' and lower level coupling'. When the phase is changed from 0 to $\pi$, the variety of spontaneous emission spectra from either of the two models are inverse to each other, in which the relative height and width of peaks are determined by the density of states in photonic crystals.
Pu Xiao-Yun, Jiang Nan, Han De-Yu, Feng Yong-Li, Ren Yi-Tao
Chin. Phys. B 2010, 19 (5): 054207;  doi: 10.1088/1674-1056/19/5/054207
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A novel Whispering--Gallery--Mode (WGM) fibre laser, emitting linearly polarised three-colour light, is demonstrated by pumping and gain coupling with evanescent waves. The pump light is longitudinally coupled into a bare optical fibre immersed in a dye solution of lower refractive index. The dye molecules around the bare fibre are excited by the evanescent waves of pump light when they propagate along the fibre in a total internal reflection. When the pump beam within the fibre is a meridian beam, the WGM lasing emission from the fibre laser is a linearly polarised transverse electric wave, while it is a mixed wave of the linearly polarised transverse electric and magnetic waves if the pump beam is a skew beam within the fibre. Because the excited molecules are located within the evanescent field of WGM, a good spatial overlap between the dye gain and the evanescent field leads to a high pumping efficiency and a longer gain distance along the fibre. Once the bare fibre is inserted into three glass capillaries filled with Rhodamine 6G, 610 and 640 dye solutions, respectively, WGM laser oscillations at the wavelengths of 567--575, 605--614 and 656--666~nm occur simultaneously, and a linearly polarised three-colour lasing emission is achieved in a single optical fibre.
Guo Wan-Hong, Liu Jun-Qi, Lu Quan-Yong, Zhang Wei, Li Lu, Wang Li-Jun, Liu Feng-Qi, Wang Zhan-Guo
Chin. Phys. B 2010, 19 (5): 054208;  doi: 10.1088/1674-1056/19/5/054208
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A 7.8-$\mu$m surface emitting second-order distributed feedback quantum cascade laser (DFB QCL) structure with metallized surface grating is studied. The modal property of this structure is described by utilizing coupled-mode theory where the coupling coefficients are derived from exact Floquet--Bloch solutions of infinite periodic structure. Based on this theory, the influence of waveguide structure and grating topography as well as device length on the laser performance is numerically investigated. The optimized surface emitting second-order DFB QCL structure design exhibits a high surface outcoupling efficiency of 22{\%} and a low threshold gain of 10~cm$^{ - 1}$. Using a {$\pi$} phase-shift in the centre of the grating, a high-quality single-lobe far-field radiation pattern is obtained.
Liu Huan, Gong Ma-Li
Chin. Phys. B 2010, 19 (5): 054209;  doi: 10.1088/1674-1056/19/5/054209
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A corner-pumped type is a new pumping type in the diode-pumped all-solid-state lasers, which has the advantages of high pump efficiency and favourable pump uniformity. A highly efficient corner-pumped Nd:YAG/YAG composite slab laser is demonstrated in this paper. The maximal continuous-wave output power of the 1064~nm laser is up to 18.57~W with a slope efficiency and an optical-to-optical conversion efficiency of 44.9{\%} and 39.8{\%}, respectively. Inserting an acousto-optic $Q$-switch in the cavity, the highest average output power of the quasi-continuous wave 1064~nm laser of 6.73~W is obtained at a repetition rate of 9.26~kHz. The experimental results show that a corner-pumped type is a kind of feasible schedules in the design of diode-pumped all-solid-state lasers with low or medium output powers.
Sun Hai-Yi, Luo Fang-Fang, HeFei, Liao Yang, Xu Jian
Chin. Phys. B 2010, 19 (5): 054210;  doi: 10.1088/1674-1056/19/5/054210
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We report on the microstructure formation in Foturan glass, induced by 1~kHz, 120 femtosecond laser irradiation. It is found that the line-shaped filamentation, not void array tends to be formed in this glass. This is different from our previous experimental results in fused silica and BK7 glasses. A possible mechanism Ag$^+$ captures the free electrons generated by laser, is proposed to explain the observed phenomena.
Zhao Jia-Yin, Wang Qi, Shen Ming, Shi Jie-Long, Kong Qian, Ge Li-Juan
Chin. Phys. B 2010, 19 (5): 054211;  doi: 10.1088/1674-1056/19/5/054211
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This paper studies the propagation of dipole solitons in highly nonlocal medium by using the variational method. It finds that the dipole solitons will be stable when the input power obeys a restrict value. When the incident power does not satisfy the stable conditions, the nonlocal accessible dipole solitons will undergo linear harmonic oscillation. It shows such evolution behaviours in detail.
Wang He-Lin, Wang Cheng, Leng Yu-Xin, Xu Zhi-Zhan, Hou Lan-Tian
Chin. Phys. B 2010, 19 (5): 054212;  doi: 10.1088/1674-1056/19/5/054212
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We report on the generation of a high energy and long pulse for pumping optical parametric chirped-pulse amplification (OPCPA) by a high-birefringence photonic crystal fibre (HB-PCF) and a laser-diode-pumped regenerative chirped pulse amplifier. Using the femtosecond pump pulse centred at 815~nm, a 1064~nm soliton pulse is produced in the HB-PCF. After injecting it into an Nd:YAG regenerative amplifier with the glass etalons, a narrow-band amplified pulse with an energy of $\sim$4~mJ and a duration of 235 ps is achieved at a repetition rate of 10~Hz, which is suitable for being used as a pump source in the 800~nm OPCPA system.
Cai Xin, Liu Jin-Song, Lü Jian-Tao
Chin. Phys. B 2010, 19 (5): 054213;  doi: 10.1088/1674-1056/19/5/054213
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Holographic dark (bright) screening solitons are predicted in one dimension for a series circuit consisting of two photorefractive crystals connected electronically by electrode leads in a chain with a voltage source. Each crystal can support a holographic screening soliton. The two solitons are known collectively as a separate holographic screening soliton pair with three types: bright--bright, bright--dark and dark--dark. The numerical results show that the two solitons in a soliton pair can affect each other through a light-induced current and their coupling can affect their spatial profiles under the limit in which the optical wave has a spatial extent much less than the width of the crystal.
Luo Bin, Hang Chao, Li Hui-Jun, Huang Guo-Xiang
Chin. Phys. B 2010, 19 (5): 054214;  doi: 10.1088/1674-1056/19/5/054214
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We study the ultraslow optical solitons in a resonant three-level atomic system via electromagnetically induced transparency under a density-matrix (DM) approach. The results of linear and nonlinear optical properties are compared with those obtained by using an amplitude variable (AV) approach. It is found that the results for both approaches are the same in the linear regime if the corresponding relations between the population-coherence decay rates in the DM approach and the energy-level decay rates in the AV approach are appropriately imposed. However, in the nonlinear regime there is a small difference for the self-phase modulation coefficient of the nonlinear Schr\"{o}dinger equation that governs the time evolution of probe pulse envelope. All analytical predicts are checked by numerical simulations.
Ye Wei-Min, Luo Zhang, Yuan Xiao-Dong, Zeng Chun
Chin. Phys. B 2010, 19 (5): 054215;  doi: 10.1088/1674-1056/19/5/054215
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Group velocity (GV) of eigenmode is a crucial parameter to explain the extraordinary phenomena about light propagation in photonic crystals (PhCs). To study relationships between group velocity and symmetry of PhCs, a new general expression of GV in PhCs made up of non-dispersive material is introduced. Based on this, the GVs of eigenmodes of PhCs, especially those of degenerate eigenmodes at highly symmetric points in the first Brillouin zone, are discussed. Some interesting results are obtained. For example, the summation of degenerate eigenmodes' GVs is invariant under the operations of wave vector ${{\bm K}}$-group $M_{{\bm K}}$. In addition, some numerical results are presented to verify them.
Lei Bo, Yang Kun-De, MaYuan-Liang
Chin. Phys. B 2010, 19 (5): 054301;  doi: 10.1088/1674-1056/19/5/054301
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Research on the underwater target scattering can provide important theoretical support for target detection. The scattering model of cylindrical shell is established in this paper. It is found that the forward target strength is much stronger and varies with angles of incident wave less significantly than backward target strength. The received forward signal strength fluctuates with the target moving due to the interference between direct signal and scattering signal, which is most significant when target approaches the baseline. An experiment is carried out in an anechoic tank to validate the scattering model. The method of acquisiting forward scattering in the tank is proposed. The forward and the backward target strengths are achieved by using the pulse compression technology, and they are about 3dB less than the modeling results. The forward scattering phenomena of quiescent and moving target are measured, which are similar to modeling results with different target types.
Huang Bei, Zhang Yan-Li, Zhang Dong, Gong Xiu-Fen
Chin. Phys. B 2010, 19 (5): 054302;  doi: 10.1088/1674-1056/19/5/054302
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This article proposes a finite element model (FEM) for predicting the acoustic scattering from an encapsulated microbubble near rigid boundary. The validity of the model is first examined by comparing the acoustic nonlinear response of a free microbubble with that obtained by the Church model. Then this model is used to investigate the effect of the rigid boundary on acoustic scattering signals from microbubble. The results indicate that the resonance frequency decreases while the oscillation amplitude increases as the microbubble approaches the rigid boundary. In addition, the fundamental component of the acoustic scattering signal is enhanced compared with that of the free microbubble.
Tang Yi-Zheng, Wu Zhao-Jun, Tang Li-Guo
Chin. Phys. B 2010, 19 (5): 054303;  doi: 10.1088/1674-1056/19/5/054303
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A spherical cap radiator is one of the important parts of an underwater wide-beam imaging system. The back radiation of a traditional spherical cap radiator, which is composed of a vibrating cap and a rigid baffle, is strong and its far-field directivity function may fluctuate in big amplitude in the vicinity of the polar axis. These shortcomings complicate the processing of the reflective waves received for imaging the targets. In this study, the back radiation is weakened by adding an acoustic soft material belt between the vibrating cap and the rigid baffle. And the fluctuation mentioned above is lowered remarkably by dividing the spherical cap radiator into many annuluses and a relatively smaller spherical cap, and by controlling the phase retardations of all elements appropriately. Furthermore, the numerical experiments are carried out by the finite element method (FEM) to prove the validity of the above methods.
Li Hai-Bin, Li Zhen
Chin. Phys. B 2010, 19 (5): 054401;  doi: 10.1088/1674-1056/19/5/054401
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We propose a new concept, the centre of energy, to study energy diffusion and heat conduction in one-dimensional hard-point model. For diatom model, we find an anomalous energy diffusion as $\langle x^2 \rangle\sim t^\beta$ with $\beta=1.33$, which is independent of initial condition and mass rate. The present model can be viewed as the model composed by independent quasi-particles, the centre of energy. In this way, heat current can be calculated. Based on theory of dynamic billiard, the divergent exponent of heat conductivity is estimated to be $\alpha=0.33$, which is confirmed by a simple numerical calculation.
PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES
Tan Zhi-Xin, Huang Yong-Sheng, Lan Xiao-Fei, Lu Jian-Xin, Duan Xiao-Jiao, Wang Lei-Jian, Yang Da-Wei, Guo Shi-Lun, Wang Nai-Yan
Chin. Phys. B 2010, 19 (5): 055201;  doi: 10.1088/1674-1056/19/5/055201
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Forward fast protons are generated by the moderate-intensity laser--foil interaction. Protons with maximum energy 190~keV are measured by using magnetic spectrometer and CR-39 solid state track detectors along the direction normal to the rear surface. The experimental results are also modeled by the particle-in-cell method, investigating the time-varying electron temperature and the rear sheath field. The temporal and spatial structure of the sheath electrical field, revealed in the simulation, suggests that these protons are accelerated by target normal sheath acceleration (TNSA) mechanism.
CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES
Lu Zhong-Lin, Zou Wen-Qin, Xu Ming-Xiang, ZhangFeng-Ming
Chin. Phys. B 2010, 19 (5): 056101;  doi: 10.1088/1674-1056/19/5/056101
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This paper reports that the high-quality Co-doped ZnO single crystalline films have been grown on $a$-plane sapphire substrates by using molecular-beam epitaxy. The as-grown films show high resistivity and non-ferromagnetism at room temperature, while they become good conductive and ferromagnetic after annealing in the reducing atmosphere either in the presence or absence of Zn vapour. The x-ray absorption studies indicate that all Co ions in these samples actually substituted into the ZnO lattice without formatting any detectable secondary phase. Compared with weak ferromagnetism (0.16~$\mu _{\rm B}$/Co$^{2 + })$ in the Zn$_{0.95}$Co$_{0.05}$O single crystalline film with reducing annealing in the absence of Zn vapour, the films annealed in the reducing atmosphere with Zn vapour are found to have much stronger ferromagnetism (0.65~$\mu _{\rm B}$/Co$^{2 + })$ at room temperature. This experimental studies clearly indicate that Zn interstitials are more effective than oxygen vacancies to activate the high-temperature ferromagnetism in Co-doped ZnO films, and the corresponding ferromagnetic mechanism is discussed.
Song Hao-Peng, Fang Qi-Hong, Liu You-Wen
Chin. Phys. B 2010, 19 (5): 056102;  doi: 10.1088/1674-1056/19/5/056102
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The interaction between a wedge disclination dipole and a crack emanating from a semi-elliptic hole is investigated. Utilising the complex variable method, the closed form solutions are derived for complex potentials and stress fields. The stress intensity factor at the tip of the crack and the image force acting on the disclination dipole center are also calculated. The influence of the morphology of the blunt crack and the position of the disclination dipole on the shielding effect to the crack and the image force is examined in detail. The results indicate that the shielding or anti-shielding effect to the stress intensity factor increases when the wedge disclination dipole approaches the tip of the crack. The effects of the morphology of the blunt crack on the stress intensity factor of the crack and the image force are very significant.
Li Xing-Ji, GengHong-Bin, Lan Mu-Jie, Yang De-Zhuang, He Shi-Yu, Liu Chao-Ming
Chin. Phys. B 2010, 19 (5): 056103;  doi: 10.1088/1674-1056/19/5/056103
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The radiation effects of the metal-oxide-semiconductor (MOS) and the bipolar devices are characterised using 8~MeV protons, 60~MeV Br ions and 1~MeV electrons. Key parameters are measured {\it in-situ} and compared for the devices. The ionising and nonionising energy losses of incident particles are calculated using the Geant4 and the stopping and range of ions in matter code. The results of the experiment and energy loss calculation for different particles show that different incident particles may give different contribution to MOS and bipolar devices. The irradiation particles, which cause larger displacement dose within the same chip depth of bipolar devices at a given total dose, would generate more severe damage to the voltage parameters of the bipolar devices. On the contrary, the irradiation particles, which cause larger ionising damage in the gate oxide, would generate more severe damage to MOS devices. In this investigation, we attempt to analyse the sensitivity to radiation damage of the different parameter of the MOS and bipolar devices by comparing the irradiation experimental data and the calculated results using Geant4 and SRIM code.
Zhao Long, Lu Peng-Fei, Yu Zhong-Yuan, Liu Yu-Min, Wang Dong-Lin, Ye Han
Chin. Phys. B 2010, 19 (5): 056104;  doi: 10.1088/1674-1056/19/5/056104
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We perform a first-principles simulation to study the electronic and optical properties of wurtzite Zn$_{1 - x}$Cu$_{x}$O. The simulations are based upon the Perdew--Burke--Ernzerhof form of generalised gradient approximation within the density functional theory. Calculations are carried out in different concentrations. With increasing Cu concentration, the band gap of Zn$_{1 - x}$Cu$_{x}$O decreases due to the shift of valence band. The imaginary part of the dielectric function indicates that the optical transition between O 2p states in the highest valence band and Zn 4s states in the lowest conduction band shifts to the low energy range as the Cu concentration increases. Besides, it is shown that the insertion of Cu atom leads to redshift of the optical absorption edge. Meanwhile, the optical constants of pure ZnO and Zn$_{0.75}$Cu$_{0.25}$O, such as loss function, refractive index and reflectivity, are discussed.
Peng Guang-Han
Chin. Phys. B 2010, 19 (5): 056401;  doi: 10.1088/1674-1056/19/5/056401
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An improved multiple car-following model is proposed by considering the arbitrary number of preceding cars, which includes both the headway and the velocity difference of multiple preceding cars. The stability condition of the extended model is obtained by using the linear stability theory. The modified Korteweg--de Vries equation is derived to describe the traffic behaviour near the critical point by applying the nonlinear analysis. Traffic flow can be also divided into three regions: stable, metastable and unstable regions. Numerical simulation is accordance with the analytical result for the model. And numerical simulation shows that the stabilisation of traffic is increasing by considering the information of more leading cars and there is unavoidable effect on traffic flow from the multiple leading cars' information.
Chen Yong-Tao, Tang Xiao-Jun, Li Qing-Zhong
Chin. Phys. B 2010, 19 (5): 056402;  doi: 10.1088/1674-1056/19/5/056402
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This paper provides an investigation of the phase transition and spalling characteristic induced during shock loading and unloading in the pure iron and the FeMnNi alloy. The impact for the pure iron is symmetric and with same-thickness for both the flyer and the target plate. It is found that an abnormal multiple spalling happens in the pure iron sample as the pressure exceeds the $\alpha -\varepsilon$ transition threshold of 13 GPa. In the symmetric and same-thickness impact and reverse impact experiments of the FeMnNi alloy, two abnormal tension regions occur when the pressure exceeds the $\alpha -\varepsilon$ transition threshold of 6.3~GPa, and the reverse phase transition $\varepsilon -\alpha$ begins below 4.2~GP. The experimental process is simulated successfully from the non-equilibrium mixture phase and Boettger's model. Such abnormal spalling phenomena are believed to relate to the shocked $\alpha -\varepsilon$ phase transition. The possible reasons for the abnormal multiple spalling, which occurs during the symmetric and same-thickness impact experiments of pure iron and FeMnNi alloy, are discussed.
Zhang Jin-Lu, Wang Li-Na, Zhou Heng-Wei, Zhang Li-Li, Zhao Xing-Yu, Huang Yi-Neng
Chin. Phys. B 2010, 19 (5): 056403;  doi: 10.1088/1674-1056/19/5/056403
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The string model for the glass transition can quantitatively describe the universal $\alpha$-relaxation in glassformers, including the average relaxation time, the distribution function of the relaxation time, and the relaxation strength as functions of temperature. The string relaxation equation (SRE) of the model, at high enough temperatures, simplifies to the well-known single particle mean-field Debye relaxation equation, and at low enough temperatures to the well-known Rouse--Zimm relaxation equation that describes the relaxation dynamics of linear macromolecules. However, its initial condition, necessary to the further model predictions of glassy dynamics, has not been solved. In this paper, the special initial condition (SIC) of the SRE, i.e. for straight strings and the dielectric spectrum technique that is one of the most common methods to measure the glassy dynamics, was solved exactly. It should be expected that the obtained SIC would benefit the solution of the general initial condition of the SRE of the string model, i.e. for stochastically spatially configurating strings, as will be described in separate publications.
Xia Ji-Hong, You Yu-Wei, WangPan-Pan, Wang Wei-Lu, Liu Chang-Song
Chin. Phys. B 2010, 19 (5): 056404;  doi: 10.1088/1674-1056/19/5/056404
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This paper performs the two-dimensional, soft-sphere molecular dynamics simulations to study the granular segregation in a binary granular mixture with the same size but different density in the container with the sawtooth base under horizontal vibration. The segregation phase diagram is presented in the acceleration-frequency space. When the acceleration is high enough to result in relative motions of the particles, the system can be in various states (mixed state, vertical and horizontal segregation state), which depend on both acceleration and frequency. Due to the sawtooth base there is stratified flow effect besides density effect. The density effect raises the light particles. The stratified flow drives the particles in the upper levels to the right and the particles in the lower particles to the left, those fact results in the appearance of the left segregation state. The left segregation state can be changed to the right segregation by changing the shape of the sawtooth. As the vibration frequency increases, the stratified flow effect becomes weaker and weaker, so at high vibration frequencies the vertical segregation state appears instead of the left segregation state.
Gong Mao-Gang, Xu Xiao-Liang, Yang Zhou, Liu Yan-Song, Liu Ling
Chin. Phys. B 2010, 19 (5): 056701;  doi: 10.1088/1674-1056/19/5/056701
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ZnO micro/nano complex structure films, including reticulate papillary nodes, petal-like and flake-hole, have been self-assembled by a hydrothermal technique at different temperatures without metal catalysts. The wettability of the above film surfaces was modified with a simple coating of heptadecafluorodecyltrimethoxy-silane in toluene. After modifying, the surface of ZnO film grown at 50~${^\circ}$C was converted from superhydrophilic with a water contact angle lower than 5$^{\circ}$ to superhydrophobic with a water contact angle of 165$^{\circ}$. Additionally, the surface of reticulate papillary nodes ZnO film grown at 100~${^\circ}$C had excellent superhydrophobicity, with a water contact angle of 173$^{\circ}$ and a sliding angle lower than 2$^{\circ}$. Furthermore, the water contact angle on the surface of petal-like and flake-hole ZnO films grown at 150~${^\circ}$C and 200~${^\circ}$C were found to be 140$^{\circ}$ and 120$^{\circ}$, respectively. The wettability for the samples was found to depend strongly on the surface morphology which results from the growth temperature.
CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES
Cheng Zhi-Da, Ling Tao, Zhu Jing
Chin. Phys. B 2010, 19 (5): 057101;  doi: 10.1088/1674-1056/19/5/057101
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Icosahedral iron clusters are synthesized and characterized in our group by using experimental methods. But the measurements of magnetic properties still face difficulties: the sizes of the clusters and the amount of product. Therefore theoretical methods are employed to study these issues. In this paper, icosahedral iron clusters containing 13, 55, 147, 309 atoms are calculated by {\em ab initio} techniques. After the structural relaxation, the magnetism of the clusters is found to be similar to that of face centred cubic (FCC) iron with stronger ferromagnetism on surface. But the central atom of each cluster is exceptional, which has a smaller magnetic moment. We also study the electronic structural properties in the clusters for the better explanation of the magnetism. It is suggested that in small clusters, the magnetic properties still depend on the local structural arrangement.
Tian Xiao-Feng, Long Chong-Sheng, Zhu Zheng-He, Gao Tao
Chin. Phys. B 2010, 19 (5): 057102;  doi: 10.1088/1674-1056/19/5/057102
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This paper performs atomic simulations of the nucleation and growth of Xe bubble in UO$_{2}$ at 1600~K. The bubble growth was simulated up to the bubble containing 50 Xe atoms. The Xe atoms were added directly to the bubble one by one, followed by a relaxation of the system for several picoseconds. The simulations estimated the bubble pressure and radius at different Xe concentrations. The results indicate that the bubble pressure drops with the increasing Xe/U and bubble size at low Xe concentration, while the pressure will increase with the Xe/U ratio at high Xe concentration. The swelling of the system associated with the bubble growth was also obtained. Finally, the recovery of the damaged structure was investigated.
Dai Jian-Feng, Mu Xiao-Wen, Qiao Xian-Wu, Chen Xiao-Ting, Wang Jun-Hong
Chin. Phys. B 2010, 19 (5): 057201;  doi: 10.1088/1674-1056/19/5/057201
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A hexagon pitch carbon nanotube (CNT) array vertical to the normal gate of cold cathode field emission displayer (FED) is simulated by solving the Laplace equation. The calculated results show that the normal gate causes the electric field around the CNT tops to be concentrated and emission electron beam become a column. The field enhancement factor and the emission current intensity step up greatly compared with those of diode structure. Emission current density increases rapidly with the decrease of normal-gate aperture. The gate voltage exerts a critical influence on the emission current.
Li Chun-Lei, Xu Yan
Chin. Phys. B 2010, 19 (5): 057202;  doi: 10.1088/1674-1056/19/5/057202
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Within the framework of the Floquet theorem, we have investigated single-electron photon-assisted tunneling in a double-well system using the transfer matrix technique. The transmission probability displays satellite peaks on the both sides of main resonance peaks and these satellite peaks originate from emission or absorption photons. The single-electron resonance tunneling can be control through changing applied harmonically potential positions, such as driven potential in wells, in barriers, or in whole double-well system. This advantage should be useful in the optimization of the parameters of a transmission device.
Xue Jun-Shuai, Hao Yue, Zhang Jin-Cheng, Ni Jin-Yu
Chin. Phys. B 2010, 19 (5): 057203;  doi: 10.1088/1674-1056/19/5/057203
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Comparative study of high and low temperature AlN interlayers and their roles in the properties of GaN epilayers prepared by means of metal organic chemical vapour deposition on (0001) plane sapphire substrates is carried out by high resolution x-ray diffraction, photoluminescence and Raman spectroscopy. It is found that the crystalline quality of GaN epilayers is improved significantly by using the high temperature AlN interlayers, which prevent the threading dislocations from extending, especially for the edge type dislocation. The analysis results based on photoluminescence and Raman measurements demonstrate that there exist more compressive stress in GaN epilayers with high temperature AlN interlayers. The band edge emission energy increases from 3.423~eV to 3.438~eV and the frequency of Raman shift of $E_{2 }$(TO) moves from 571.3~cm$^{ - 1}$ to 572.9~cm$^{ - 1}$ when the temperature of AlN interlayers increases from 700~$^{\circ}$C to 1050~$^{\circ}$C. It is believed that the temperature of AlN interlayers effectively determines the size, the density and the coalescence rate of the islands, and the high temperature AlN interlayers provide large size and low density islands for GaN epilayer growth and the threading dislocations are bent and interactive easily. Due to the threading dislocation reduction in GaN epilayers with high temperature AlN interlayers, the approaches of strain relaxation reduce drastically, and thus the compressive stress in GaN epilayers with high temperature AlN interlayers is high compared with that in GaN epilayers with low temperature AlN interlayers.
Liu Xing-Hua, Lu Wen-Sheng, Ji Zhuo-Yu, Tu De-Yu, Zhu Xiao-Li, Xie Chang-Qing, Liu Ming
Chin. Phys. B 2010, 19 (5): 057204;  doi: 10.1088/1674-1056/19/5/057204
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This paper reports a procedure of soft x-ray lithography for the fabrication of organic crossbar structure. Electron beam lithography is employed to fabricate the mask for soft x-ray lithography, with direct writing technology to lithograph positive resist, polymethyl methacrylate on the polyimide film. Then Au is electroplated on the polyimide film. Hard contact mode exposure is used in x-ray lithography to transfer the graph from the mask to the wafer. The 256-bits organic memory is achieved with the critical dimension of 250~nm.
Chen Yong-Sheng, Yang Shi-E, Wang Jian-Hua, Lu Jing-Xiao, Gao Xiao-Yong, Gu Jin-Hua
Chin. Phys. B 2010, 19 (5): 057205;  doi: 10.1088/1674-1056/19/5/057205
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This paper studies the effects of silane back diffusion in the initial plasma ignition stage on the properties of microcrystalline silicon ($\mu$c-Si:H) films by Raman spectroscopy and spectroscopic ellipsometry, through delaying the injection of SiH$_{4}$ gas to the reactor before plasma ignition. By comparing with standard discharge condition, delayed SiH$_{4}$ gas condition could prevent the back diffusion of SiH$_{4}$ from the reactor to the deposition region effectively, which induced the formation of a thick amorphous incubation layer in the interface between bulk film and glass substrate. Applying this method, it obtains the improvement of spectral response in the middle and long wavelength region by combining this method with solar cell fabrication. Finally, results are explained by modifying zero-order analytical model, and a good agreement is found between model and experiments concerning the optimum delayed injection time.
Liu Hong
Chin. Phys. B 2010, 19 (5): 057206;  doi: 10.1088/1674-1056/19/5/057206
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This paper studies the quantum conductance properties of three-terminated carbon nanotube Y-junctions, which are built by connecting three (5,5) single-walled carbon nanotubes. The results show that the quantum conductance at the Fermi energy oscillates periodically with the junction's size, and the number of oscillating periodic layers is 3 which is the same as that in the two terminated $(10,0)/m(5,5)/(10,0)$ junctions. Moreover, this Y-junction with different size exhibits obvious different distribution of electron current in the two drain branches, called shunt valve effect of electronic current. Thus the degree of this effect can be controlled and modulated directly by constructing the three branches' sizes or the distribution of defect. The results show in detail that the difference between the two drain currents can be up to two times for some constructions with special sizes. In addition, the uniform distribution of defects in the Y-junction leads to lower quantum conductance than that of other defect configurations.
Su Jie, Wang Ji-Suo, Zhang Xiao-Yan, Liang Bao-Long
Chin. Phys. B 2010, 19 (5): 057301;  doi: 10.1088/1674-1056/19/5/057301
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For a mesoscopic radio frequency superconducting quantum interference device (rfSQUID), at a degeneracy point, the system reduces to a quantum two-state system which can be used as a flux qubit. When the noise environment is equivalent to a harmonic oscillators bath, by virtue of an operator-norm measure for the short time decoherence, this paper investigates the initial decoherence of the flux qubit operating in the ohmic noise environment and illustrates its property by means of the numerical evaluation.
Hu Ai-Bin, Xu Qiu-Xia
Chin. Phys. B 2010, 19 (5): 057302;  doi: 10.1088/1674-1056/19/5/057302
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Ge and Si p-channel metal--oxide--semiconductor field-effect-transistors (p-MOSFETs) with hafnium silicon oxynitride (HfSiON) gate dielectric and tantalum nitride (TaN) metal gate are fabricated. Self-isolated ring-type transistor structures with two masks are employed. W/TaN metal stacks are used as gate electrode and shadow masks of source/drain implantation separately. Capacitance--voltage curve hysteresis of Ge metal--oxide--semiconductor (MOS) capacitors may be caused by charge trapping centres in GeO$_{x}$ ($1 Liu Hong-Xia, Wu Xiao-Feng, Hu Shi-Gang, Shi Li-Chun Chin. Phys. B 2010, 19 (5): 057303; doi: 10.1088/1674-1056/19/5/057303 Full Text: PDF (735KB) ( 630 ) Show Abstract Current transport mechanism in Ni-germanide/n-type Ge Schottky diodes is investigated using current--voltage characterisation technique with annealing temperatures from 300~\duto 500~\du. Based on the current transport model, a simple method to extract parameters of the NiGe/Ge diode is presented by using the$I$--$V$characteristics. Parameters of NiGe/n-type Ge Schottky diodes fabricated for testing in this paper are as follows: the ideality factor$n$, the series resistance$R_{\rm s}$, the zero-field barrier height$\phi _{\rm b0}$, the interface state density$D_{\rm it}$, and the interfacial layer capacitance$C_{\rm i}$. It is found that the ideality factor$n$of the diode increases with the increase of annealing temperature. As the temperature increases, the interface defects from the sputtering damage and the penetration of metallic states into the Ge energy gap are passivated, thus improving the junction quality. However, the undesirable crystallisations of Ni-germanide are observed together with NiGe at a temperature higher than 400~\du. Depositing a very thin ($\sim $1~nm) heavily Ge-doped$n^{+}$Ge intermediate layer can improve the NiGe film morphology significantly. Du Gang, Liu Xiao-Yan, Xia Zhi-Liang, Yang Jing-Feng, Han Ru-Qi Chin. Phys. B 2010, 19 (5): 057304; doi: 10.1088/1674-1056/19/5/057304 Full Text: PDF (289KB) ( 552 ) Show Abstract Interface roughness strongly influences the performance of germanium metal--organic--semiconductor field effect transistors (MOSFETs). In this paper, a 2D full-band Monte Carlo simulator is used to study the impact of interface roughness scattering on electron and hole transport properties in long- and short- channel Ge MOSFETs inversion layers. The carrier effective mobility in the channel of Ge MOSFETs and the in non-equilibrium transport properties are investigated. Results show that both electron and hole mobility are strongly influenced by interface roughness scattering. The output curves for 50~nm channel-length double gate n and p Ge MOSFET show that the drive currents of n- and p-Ge MOSFETs have significant improvement compared with that of Si n- and p-MOSFETs with smooth interface between channel and gate dielectric. The$82\%$and$96\%$drive current enhancement are obtained for the n- and p-MOSFETs with the completely smooth interface. However, the enhancement decreases sharply with the increase of interface roughness. With the very rough interface, the drive currents of Ge MOSFETs are even less than that of Si MOSFETs. Moreover, the significant velocity overshoot also has been found in Ge MOSFETs. E. Yüzüak, B. Emre, Y. Elerman, A. Yücel Chin. Phys. B 2010, 19 (5): 057501; doi: 10.1088/1674-1056/19/5/057501 Full Text: PDF (1252KB) ( 436 ) Show Abstract The crystal structure, magnetic and magnetocaloric characteristics of the pseduo ternary compounds of Tb$_{5}$Ge$_{2-x}$Si$_{2-x}$Mn$_{2x}$(0$\leq $2$x\leq$0.1) were investigated by x-ray powder diffraction and magnetization measurements. The x-ray powder diffraction results show that all compounds preserve the monoclinic phase as the majority phase and all the synthesized compounds were observed to be ferromagnetic from magnetization measurements. Magnetic phase transitions were interpreted in terms of Landau theory. Maximum isothermal magnetic entropy change value (20.84~J\,$\cdot$\,kg$^{-1}$\,$\cdot$\,K$^{-1}$) was found for Tb$_{5}$Ge$_{1.95}$Si$_{1.95}$Mn$_{0.1}$at around 123~K in the magnetic field change of 5~T. Yin Jin-Hua, Pan Li-Qing Chin. Phys. B 2010, 19 (5): 057502; doi: 10.1088/1674-1056/19/5/057502 Full Text: PDF (2306KB) ( 488 ) Show Abstract The interaction and its variation between magnetic grains in two kinds of magnetic recording tapes are investigated by first-order reversal curves (FORC) and the$\delta M$method. The composition and microstructure of the samples are characterised by x-ray diffraction and scanning electron microscope. The FORC diagram can provide more accurate information of the interaction and its variation, but the$\delta M$curves cannot. The positive interaction field and the large variation of the interaction field have opposite effects on the$\delta M$curve. Ye Chao, Ning Zhao-Yuan Chin. Phys. B 2010, 19 (5): 057701; doi: 10.1088/1674-1056/19/5/057701 Full Text: PDF (209KB) ( 586 ) Show Abstract This paper investigates the capacitance--voltage ($C$--$V$) characteristics of F doping SiCOH low dielectric constant films metal--insulator--semiconductor structure. The F doping SiCOH films are deposited by decamethylcyclopentasiloxane (DMCPS) and trifluromethane (CHF$_{3})$electron cyclotron resonance plasmas. With the CHF$_{3}$/DMCPS flow rate ratio from 0 to 0.52, the positive excursion of$C$--$V$curves and the increase of flat-band voltage$V_{\rm FB}$from$-6.1$~V to 32.2~V are obtained. The excursion of$C$--$V$curves and the shift of$V_{\rm FB}$are related to the change of defects density and type at the Si/SiCOH interface due to the decrease of Si and O concentrations, and the increase of F concentration. At the CHF$_{3}$/DMCPS flow rate ratio is 0.12, the compensation of F-bonding dangling bond to Si dangling bond leads to a small$V_{\rm FB}$of 2.0~V. Wei Jing-Song, Xiao Mu-Fei Chin. Phys. B 2010, 19 (5): 057801; doi: 10.1088/1674-1056/19/5/057801 Full Text: PDF (1128KB) ( 504 ) Show Abstract We present a detailed theoretical analysis on the possibilities and conditions for negative permeability and negative refraction occuring in the magnetic materials with both pronounced magnetic and dielectric responses to electromagnetic waves. The results indicate that the permeability is always positive for$\de=(2q+0.5)\pi$($\de$is the initial phase difference of magnetic components$h_{x}$and$h_{y }$of incident electromagnetic wave,$q$is integer), which means that it is difficult to realize negative refraction. However, for$\de=2q\pi, \de=(2q+1)\pi$, or$\de=(2q-0.5)\pi$, the negative permeability occurs at some range of free procession frequency, which means that the refraction can become negative under certain conditions. Further analysis reveals that for general positive permittivity there are various opportunities for realizing the negative refraction provided that some requirements are met. One concludes also that the refractive index for$\de=2q\pi$case is similar to$\de=(2q+1)\pi$. The only difference between two cases of$\de=2q\pi$and$\de=(2q+1)\pi$is that the$x$-direction for$\de=2q\pi$corresponds to the$y$-direction for$\de=(2q+1)\pi$, and the$y$-direction for$\de=2q\pi$corresponds to the$x$-direction for$\de=(2q+1)\pi$. The results are valuable for designing and analysing the complex negative refraction of magnetic materials. Zhao De-Gang, Zhang Shuang, Liu Wen-Bao, Jiang De-Sheng, Zhu Jian-Jun, Liu Zong-Shun, Wang Hui, Zhang Shu-Ming, Yang Hui, Hao Xiao-Peng, Wei Long Chin. Phys. B 2010, 19 (5): 057802; doi: 10.1088/1674-1056/19/5/057802 Full Text: PDF (327KB) ( 848 ) Show Abstract The leakage current of GaN Schottky barrier ultraviolet photodetectors is investigated. It is found that the photodetectors adopting undoped GaN instead of lightly Si-doped GaN as an active layer show a much lower leakage current even when they have a higher dislocation density. It is also found that the density of Ga vacancies in undoped GaN is much lower than in Si-doped GaN. The Ga vacancies may enhance tunneling and reduce effective Schottky barrier height, leading to an increase of leakage current. It suggests that when undoped GaN is used as the active layer, it is necessary to reduce the leakage current of GaN Schottky barrier ultraviolet photodetector. Ci Zhi-Peng, Wang Yu-Hua, Zhang Jia-Chi Chin. Phys. B 2010, 19 (5): 057803; doi: 10.1088/1674-1056/19/5/057803 Full Text: PDF (194KB) ( 1179 ) Show Abstract Novel Y$_{1 - x - y}$VO$_{4}$:$x$Dy$^{3 + }$,$y$Bi$^{3 + }$($0.01 \le x \le 0.05, 0 \le y \le 0.20$) phosphors for light emitting diode (LED) were successfully synthesised by solid-state reaction. The calculation results of electronic structure show that YVO$_{4}$has a direct band gap with 3~eV at$G$. The top of the valence band is dominated by O 2p state and the bottom of the conduction band is mainly composed of O 2p and V 3d states. An efficient yellow emission under near-ultraviolet (365 nm) excitation is observed. Compared with the pure YVO$_{4}$:Dy$^{3 + }$samples, the Dy$^{3 + }$, Bi$^{3 + }$co-doped samples show a more intensive emission peak (at 574~nm) and a new broad emission band (450--770~nm), due to the$^{4}F_{9 / 2}-{}^{6}H_{13 / 2 }$transition of Dy$^{3 + }$and the emission of the VO$_{4}^{3 - }-$Bi$^{3 + }$complex respectively. The optimum chromaticity index of Y$_{1 - x - y}$VO$_{4}$:$x$Dy$^{3 + }$,$y$Bi$^{3 + }$($0.01 \le x \le 0.05, 0 \le y \le 0.20$) is (0.447, 0.497), which indicates that YVO$_{4}$:Dy$^{3 + }$, Bi$^{3 + }$has higher colour saturation than the commercial phosphor YAG: Ce$^{3 + }$. The effects of concentration of Dy$^{3 + }$, Bi$^{3 + }\$, electric states and the photoluminescence properties are discussed in details.
8000 CROSSDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY
GEOPHYSICS, ASTRONOMY, AND ASTROPHYSICS
Xie Tao, Zou Guang-Hui, WilliamPerrie, Kuang Hai-Lan, Chen Wei
Chin. Phys. B 2010, 19 (5): 059201;  doi: 10.1088/1674-1056/19/5/059201
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Using the theory of nonlinear interactions between long and short waves, a nonlinear fractal sea surface model is presented for a one dimensional deep sea. Numerical simulation results show that spectra intensity changes at different locations (in both the wave number domain and temporal-frequency domain), and the system obeys the energy conservation principle. Finally, a method to limit the fractal parameters is also presented to ensure that the model system does not become ill-posed.
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