首页 | 本学科首页   官方微博 | 高级检索  
     检索      


Diffusion in a periodic potential with a local perturbation
Authors:K Golden  S Goldstein  J L Lebowitz
Institution:(1) Department of Mathematics, Rutgers University, 08903 New Brunswick, New Jersey;(2) Present address: Department of Mathematics, Princeton University, 08544 Princeton, New Jersey;(3) Department of Physics, Rutgers University, 08903 New Brunswick, New Jersey
Abstract:We consider the diffusion of a particle at Xt in a drift field derived from a smooth potential of the formV+B, whereV is periodic andB is a bump of compact support. With no bump,B=0, the mean squared displacementE(t) equivE |X t – X0|2 =D(V)t +C +O(e lambdat ),lambda>0, in any dimension. WhenBne0, we establish in one dimension the asymptotic expansion 
$$E(t) = D(V)t + \alpha \sqrt t  + C + (1/\sqrt t )\sum _{n = 0}^\infty  \alpha _n /t^n $$
, agrne0, astrarrinfin. Our analysis relies on the Nash estimates developed in previous work for the transition density of the process and their consequences for the analytic structure,of the Laplace transform 
$$\tilde E(s)$$
ofE(t).
Keywords:Diffusion  periodic potential  local perturbation  Nash estimates  mean squared displacement  velocity autocorrelation function
本文献已被 SpringerLink 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号