17 December 2024
Bari, Sezione INFN e Dipartimento Interateneo di Fisica
Europe/Rome timezone

Two-states Ornstein-Uhlenbeck particle in a trapping potential

17 Dec 2024, 10:10
20m
Aula A "Giuseppe Nardulli" (Bari, Sezione INFN e Dipartimento Interateneo di Fisica)

Aula A "Giuseppe Nardulli"

Bari, Sezione INFN e Dipartimento Interateneo di Fisica

Speaker

Daniela Moretti (Istituto Nazionale di Fisica Nucleare)

Description

In recent years, much attention has been paid to the observation of non-Gaussian probability density functions for diffusing systems in a variety of experiments and theoretical models, as such property could entail new physical insight. In this work, we solved analytically the Langevin equation of motion in the overdamped regime of a particle moving both in absence and in presence of a harmonic potential, assuming the diffusion coefficient to be a Telegraph Process, i.e. the diffusion coefficient changes stochastically between two states. We computed analytically the first four momenta of the distribution of the particle position observing a non-Gaussian behaviour for short times. We found that the duration of the non-Gaussian behaviour decreases with the strength of the confinement and increases with the increasing of the microscopic time scale of the subordinating process. The relations we determined can become a very useful tool in experiments to determine the value of the unknown microscopic time scale starting from the value of kurtosis.

Primary authors

Daniela Moretti (Istituto Nazionale di Fisica Nucleare) Giovanni Battista Carollo (Istituto Nazionale di Fisica Nucleare)

Co-authors

Giuseppe Gonnella (Istituto Nazionale di Fisica Nucleare) Antonio Suma (SISSA) Enzo Orlandini (PD) Prof. Fulvio Baldovin ((Università degli Studi di Padova - Dipartimento di Fisica "G. Galilei"))

Presentation materials