Effects of signal modulation and coloured cross-correlation of coloured noises on the diffusion of a harmonic oscillator
Liu Li(刘立)a), Zhang Liang-Ying(张良英)b), and Cao Li(曹力)a)†
a School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China; b Department of Physics & Electronics Information Technology, Xiangfan University, Xiangfan 441053, China
AbstractThe diffusion in a harmonic oscillator driven by coloured noises $\xi(t)$ and $\eta(t)$ with coloured cross-correlation in which one of the noises is modulated by a biased periodic signal is investigated. The exact expression of diffusion coefficient d as a function of noise parameter, signal parameter, and oscillator frequency is derived. The findings in this paper are as follows. 1) The curves of d versus noise intensity D and d versus noises cross-correlation time $\tau_3$ exist as two different phases. The transition between the two phases arises from the change of the cross-correlation coefficient $\lambda$ of the two Ornstein--Uhlenbeck (O-U) noises. 2) Changing the value of $\tau_3$, the curves of dversus Q, the intensity of colored noise that is modulated by the signal, can transform from a phase having a minimum to a monotonic phase. 3) Changing the value of signal amplitude A, d versus Q curves can transform from a phase having a minimum to a monotonic phase. The above-mentioned results demonstrate that a like noise-induced transition appears in the model.
Received: 14 April 2009
Revised: 27 April 2009
Accepted manuscript online:
Fund: Project supported by the National
Natural Science Foundation of
China (Grant No 10275025).
Cite this article:
Liu Li(刘立), Zhang Liang-Ying(张良英), and Cao Li(曹力) Effects of signal modulation and coloured cross-correlation of coloured noises on the diffusion of a harmonic oscillator 2009 Chin. Phys. B 18 4182
Preliminary analysis of impurity transport in HL-2A ohmic discharges Chen Wei(陈伟), Cui Zheng-Ying(崔正英), Sun Ping(孙平), Huang Yuan(黄渊), Zhang Peng(张鹏), Deng Wei(邓玮), Pan Yu-Dong(潘宇东), Shi Zhong-Bing(石中兵), Zhou Yan(周艳), Zheng Yong-Zhen(郑永真), and Yang Qing-Wei(杨青巍). Chin. Phys. B, 2007, 16(11): 3451-3457.
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.
