Sarracino A
CNR-ISC and Dipartimento di Fisica, Università Sapienza, p.le A. Moro 2, 00185 Roma, Italy.
Phys Rev E Stat Nonlin Soft Matter Phys. 2013 Nov;88(5):052124. doi: 10.1103/PhysRevE.88.052124. Epub 2013 Nov 19.
We show by numerical simulations that the presence of nonlinear velocity-dependent friction forces can induce a finite net drift in the stochastic motion of a particle in contact with an equilibrium thermal bath and in an asymmetric periodic spatial potential. In particular, we study the Kramers equation for a particle subjected to Coulomb friction, namely a constant force acting in the direction opposite to the particle's velocity. We characterize the nonequilibrium irreversible dynamics by studying the generalized fluctuation-dissipation relation for this ratchet model driven by Coulomb friction.
我们通过数值模拟表明，与平衡热浴接触且处于非对称周期性空间势中的粒子，其随机运动中存在与速度相关的非线性摩擦力会诱导有限的净漂移。特别地，我们研究了受库仑摩擦作用的粒子的克莱默斯方程，即一个与粒子速度方向相反的恒力。我们通过研究由库仑摩擦驱动的这个棘轮模型的广义涨落耗散关系来刻画非平衡不可逆动力学。
