摘要
在非磁化的直流放电等离子体中,利用系统内禀的周期驱动力与外加的高斯白噪声的协同作用,成功地在系统动力学轨道Hopf分岔的不动点一侧,观察到了周期信号的信噪比被噪声改善的随机共振现象.一维过阻尼系统的随机共振模型可以解释所观察的实验结果.比较实验结果与理论模型可知,系统动力学轨道发生Hopf分岔的原因是系统双稳态之间势垒的变化;在Hopf分岔的极限环一侧观察不到随机共振现象。
Stochastic resonance phenomena have been studied in a non\|magnetized plasma.A white Gaussian noise is externally applied to coherently interact with the intrinsic periodic driven force of the system.Signal\|to\|noise ratio is improved by external noise in the fixed\|point region near a Hopf bifurcation of the system.The experimental results are consistent with the predictions given by one\|dimensional stochastic resonance model for an over\|damping bistable system.Hopf bifurcation is found to be caused by the variation of the potential barrier of the system.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2000年第3期508-512,共5页
Acta Physica Sinica
基金
国家自然科学基金 (批准号 :1983 5 0 2 0 )和国家攀登计划 (非线性科学 )基金资助的课题
