Quantum dynamics in lattices in presence of bulk dephasing and a localized source

TL;DR

This paper investigates the dynamics of one-dimensional quantum lattices with a localized source under bulk dephasing, revealing complex behaviors and scaling laws through analytical and numerical methods relevant to quantum simulation.

Contribution

It introduces a combined analytical and numerical study of quantum lattice dynamics with a localized source and bulk dephasing, including long-range hopping and interactions, highlighting rich dynamical phenomena.

Findings

Universal dynamical scaling observed

Anomalous behavior across different time scales

Analytical insights for non-interacting case

Abstract

The aim of this work is to study the dynamics of quantum systems subjected to a localized fermionic source in the presence of bulk dephasing. We consider two classes of one-dimensional lattice systems: (i) a non-interacting lattice with nearest-neighbor and beyond, i.e., long-ranged (power-law) hopping, and (ii) a lattice that is interacting via short-range interactions modeled by a fermionic quartic Hamiltonian. We study the evolution of the local density profile $n_i(t)$ within the system and the growth of the total particle number $N(t)$ in it. For case (i), we provide analytical insights into the dynamics of the nearest-neighbor model using an adiabatic approximation, which relies on assuming faster relaxation of coherences of the single particle density matrix. For case (ii), we perform numerical computations using the time-evolving block decimation (TEBD) algorithm and analyze the density profile and the growth exponent in $N(t)$. Our detailed study reveals an interesting interplay between Hamiltonian dynamics and various environmentally induced mechanisms in open quantum systems, such as local source and bulk dephasing. It brings out rich dynamics, including universal dynamical scaling and anomalous behavior across various time scales and is of relevance to various quantum simulation platforms.