The relation between noise and Fick's diffusion coefficient in barrier limited transport associated with hopping or tunnelling mechanisms of particles exhibiting the asymmetric simple exclusion processes (ASEP) is physically assessed by means of Monte Carlo simulations. For a closed ring consisting of a large number of barriers the diffusion coefficient is related explicitly to the current noise, thus revealing the existence of a generalized Nyquist-Einstein relation. Both diffusion and noise are confirmed to decrease as the square root of the number of barriers as a consequence of the correlation induced by ASEP. By contrast, for an open linear chain of barriers the diffusion coefficient is found to be no longer related to current noise. Here diffusion depends on particle concentration but is independent of the number of barriers.
A Monte Carlo investigation of noise and diffusion of particles exhibiting asymmetric exclusion processes
2007
Abstract
The relation between noise and Fick's diffusion coefficient in barrier limited transport associated with hopping or tunnelling mechanisms of particles exhibiting the asymmetric simple exclusion processes (ASEP) is physically assessed by means of Monte Carlo simulations. For a closed ring consisting of a large number of barriers the diffusion coefficient is related explicitly to the current noise, thus revealing the existence of a generalized Nyquist-Einstein relation. Both diffusion and noise are confirmed to decrease as the square root of the number of barriers as a consequence of the correlation induced by ASEP. By contrast, for an open linear chain of barriers the diffusion coefficient is found to be no longer related to current noise. Here diffusion depends on particle concentration but is independent of the number of barriers.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
