[an error occurred while processing this directive]
[an error occurred while processing this directive]
Chin. Phys. B  
  Chin. Phys. B--1995, Vol.4, No.11
Select | Export to EndNote
GENERAL

REALIZATION OF THE WAVE-PACKET-COLLAPSE —A VIEWPOINT TO THE QUANTUM MEASUREMENT THEORY

DUAN LU-MING, GUO GUANG-CAN
Chin. Phys. B 1995, 4 (11): 801 ;  doi: 10.1088/1004-423X/4/11/001
Full Text: PDF (122KB) ( 304 )
Show Abstract
An interpretion of the wave-packet-collapse (WPC) in the system of quantum mechanics is given. We find a connection between the WPC and the limitation to the measurement precision determined by the quantum fluctuation. A simple and explicit relation about them is obtained.

NORMAL-INCIDENCE QUANTUM WELL INFRARED PHOTODETECTOR WITHOUT GRATING COUPLER

WANG WEN-XIN, HU QIANG, HUANG QI, ZHOU JUN-MING, CUI DA-FU, CHEN ZHENG-HAO
Chin. Phys. B 1995, 4 (11): 806 ;  doi: 10.1088/1004-423X/4/11/002
Full Text: PDF (106KB) ( 363 )
Show Abstract
The n-type GaAs/AlxGa1-xAs multiple quantum well infrared photodetectors have been demonstrated without any grating couplers. We have achieved a responsivity Rv of 1.7×105V/W and a detectivity Dλ* of 4.0×1010 cm (Hz)1/2/W for a wavelength of 8.4 μm at a temperature T = 77 K in normal incidence.
CLASSICAL AREAS OF PHENOMENOLOGY

EFFECTIVE CAVITY LENGTH IN VERTICAL CAVITY SURFACE EMITTING LASER

PAN ZHONG, WU RONG-HAN, WANG QI-MING
Chin. Phys. B 1995, 4 (11): 810 ;  doi: 10.1088/1004-423X/4/11/003
Full Text: PDF (148KB) ( 282 )
Show Abstract
Effective cavity length method is introduced to vertical cavity surface emitting laser for characterizing some properties, including reflectivity, FWHM, mode wavelength and thresh-old gain. Some experiment results are demonstrated, showing the agreement of theoretical analysis with experiment.
CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES

GENERALIZATION OF ESHELBY'S METHOD TO THE ANISOTROPIC ELASTICITY THEORY OF DISLOCATIONS IN QUASICRYSTALS

DING DI-HUA, QIN YUE-LING, WANG REN-HUI, HU CHENG-ZHENG, YANG WEN-GE
Chin. Phys. B 1995, 4 (11): 816 ;  doi: 10.1088/1004-423X/4/11/004
Full Text: PDF (217KB) ( 348 )
Show Abstract
The general expressions of the elastic fields induced by straight dislocations in quasicrystals have been given according to Eshelby's method which was used to treat the anisotropic elasticity of dislocations in crystals. As an example, the elastic displacement vector, the stress tensor and the elastic energy density of a screw dislocation line lying on the quasiperiodic plane of decagonal quasicrystals are calculated.

GAS DYNAMIC PROBLEMS CAUSED BY THE GENERATION OF THE RADICALS IN A SUPERSONIC JET

LIU SHI-LIN, ZHANG LI-MIN, CHEN CONG-XIANG, MA XING-XIAO, ZHU NIAN-LIN
Chin. Phys. B 1995, 4 (11): 825 ;  doi: 10.1088/1004-423X/4/11/005
Full Text: PDF (223KB) ( 315 )
Show Abstract
A simplified one-dimensional model was proposed to treat the gas dynamic problems in a supersonic jet, which was used to produce radicals cooled by supersonic expansion, Based on this model, the gas dynamic equations can be integrated directly to obtain the evolution or the translational temperature and the rotational temperature of free radicals as well as the molecule density. The results show that the heating position where the radicals are generated and the initial rotational temperature of radicals have little effect on the rotational temperature at the down stream detection point, if the heating position is close to the nozzle orifice.
CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES

BAND STRUCTURES OF Si-C AND Si-C-Ge ALLOYS

XIE JIAN-JUN, ZHANG KAI-MING
Chin. Phys. B 1995, 4 (11): 834 ;  doi: 10.1088/1004-423X/4/11/006
Full Text: PDF (251KB) ( 271 )
Show Abstract
Band structures of Si-C and Si-C-Ge alloys are calculated by using the ab initio LMTO (linear muffin-tin orbital) method within the framework of atomic-sphere approximation. The effects of different atomic configuration and lattice relaxation on the band structure of alloys are taken into account. The results show that for large concentrations of C in Si and Si-Ge, the band gap increases monotonically, while for small concentrations of C in Si and Si-Ge, the band gap shrinks. The lattice relaxation further reduces the band gap. The possible explanations for the reduction of band gap of Si-C and Si-C-Ge alloya are presented.

CRITICAL EXPONENTS OF THE ONE-DIMENSIONAL CONTINUUM HEISENBERG-ISING MODEL

ZHANG YU-MEI, XU BO-WEI
Chin. Phys. B 1995, 4 (11): 842 ;  doi: 10.1088/1004-423X/4/11/007
Full Text: PDF (122KB) ( 288 )
Show Abstract
The continuum generalization of the one-dimensional Heisenberg-Ising model is studied by the bosonization method. With reference to the results of the renormalization group theory, we are able to obtain the critical exponents by considering the influence of the large momentum transfer and improve Luther and Peschel's results to the next order. A comparison of the exact result of the lattice model with that of the continuum model by various treatments are also given.

MULTI-ACTIVATION ENERGY DENSITY DISTRIBUTION AND THERMALLY STIMULATED CURRENT OF ELECTRIC DIPOLES IN CONDENSED MATTER

LIU FU-DE, LING ZHI-YUAN, XIONG MAO-REN
Chin. Phys. B 1995, 4 (11): 847 ;  doi: 10.1088/1004-423X/4/11/008
Full Text: PDF (215KB) ( 271 )
Show Abstract
The physical meaning of the transcendental function in traditional thermally stimulated current (TSC) equation of electric dipoles with a single activation energy was first analyzed. Then a simple formula obtained directly from the tested TSC for calculating activation energy parameter, etc., was deduced. Numerical calculation showed that the exact TSC agrees with the approximated one very well. Further analysis found a limiting condition for the discrete to continuous activation energy density distribution and a criterion for discriminating the contributions to TSC by depolarization of the dipoles with multi-activation energy from those with a single one.

ELECTROLUMINESCENCE SPECTRA OF GexSi1-x/Si SINGLE QUANTUM WELL

CHENG WEN-QIN, CUI QIAN, CAI LI-HONG, HU QIANG, ZHOU JUN-MING
Chin. Phys. B 1995, 4 (11): 856 ;  doi: 10.1088/1004-423X/4/11/009
Full Text: PDF (74KB) ( 296 )
Show Abstract
The electroluminescence of GexSi1-x/Si single quantum well was measured at temper-atures above room temperature along the growth direction and the direction normal to it. TO and NP peaks were resolved.

RAMAN SCATTERING OF ORGANIC CHARGE-TRANSFER SALTS CONTAINING BEDT-TTF CATION

LIU DAO-ZHI
Chin. Phys. B 1995, 4 (11): 864 ;  doi: 10.1088/1004-423X/4/11/011
Full Text: PDF (176KB) ( 299 )
Show Abstract
Raman scattering of several organic charge-transfer salts containing BEDT-TTF of ET cation such as κ-ET2Cu(NCS)2, βL-ET2I3, α-ET3Cl2. 2H2O, a-ET3 (ReO4)2 and ETFeBr4 were measured and the variations of the frequencies of C=C bonds of ET molecules on charge transfer were observed. It is found that the energy of C=C stretch modes shows a general downward shift upon ionisation of ET molecule. In addition, we have observed the Raman spectra of C=C stretch vibratinns in κ-ET2Cu(NCS)2 single crystal on going through Tc(~10.4 K) and found no detectable effect during the superconducting phase transition.
8000 CROSSDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY
[an error occurred while processing this directive]