Superdiffusive Transport in Quasi-Particle Dephasing Models

TL;DR

This paper demonstrates that local dephasing in noninteracting fermions can cause superdiffusive transport due to long-lived modes linked to quasi-particle properties, with implications for higher-dimensional systems.

Contribution

It reveals a mechanism for superdiffusion driven by quasi-particle dephasing and long-lived modes, extending understanding of transport phenomena in quantum systems.

Findings

Superdiffusive transport arises from nodal points in momentum distribution.

Long-lived modes lead to Levy walk dynamics.

Controllability of dynamical exponents by quasi-particle selection.

Abstract

Investigating the behavior of noninteracting fermions subjected to local dephasing, we reveal that quasi-particle dephasing can induce superdiffusive transport. This superdiffusion arises from nodal points within the momentum distribution of local dephasing quasi-particles, leading to asymptotic long-lived modes. By studying the dynamics of the Wigner function, we rigorously elucidate how the dynamics of these enduring modes give rise to L\'evy walk processes, a renowned mechanism underlying superdiffusion phenomena. Our research demonstrates the controllability of dynamical scaling exponents by selecting quasi-particles and extends its applicability to higher dimensions, underlining the pervasive nature of superdiffusion in dephasing models.