由双不动点映射生成的乘性类Langevin噪声驱动的过阻尼分数阶棘齿

本文研究双不动点映射生成的乘性类Langevin噪声驱动的过阻尼分数阶波动势模型的定向输运,其中的确定性类Langevin噪声是混沌噪声的自然推广,由仅具有两个不动点的逐段单调映射迭代产生.数值模拟结果显示:当模型同时空、时对称破缺时定向流出现,且噪声参数的变化可以引起定向流的振荡、衰减与逆转.值得注意的是该定向输运行并不依赖于热扩散,即棘齿是非热的.

Overdamped fractional ratchets driven by multiplicative Langevin-like noises generated by mappings with two fixed points

We numerically study the directed transport of an overdamped fractional fluctuating potential model driven by multiplicative Langevin like noise generated by a piecewise monotonic mapping having only two fixed points. Here the Langevin like noise is a natural generalization of chaotic noise. It is shown that, in the presence of spatial asymmetry of the substrate potential, temporal asymmetry of the Langevin like noise can induce net current, and the varieties of the parameters of noise can result in oscillating decay and multi inverse currents without the presence of thermal noise, therefore the ratchet is nonthermal.