Adiabatic Tracking of a State: a New Route to Nonequilibrium Physics

TL;DR

This paper introduces a new numerical method to study the response of quantum systems to gradual external perturbations, enabling access to highly excited states and their entanglement properties.

Contribution

A novel adiabatic tracking protocol integrated with DMRG to explore excited states and entanglement in interacting fermionic systems under magnetic flux.

Findings

Successfully tracked current-carrying excited states.

Connected entanglement entropy with nonequilibrium states.

Demonstrated effectiveness in one-dimensional fermionic systems.

Abstract

We present a novel numerical approach to track the response of a quantum system to an external perturbation that is progressively switched-on. The method is applied, within the framework of the density matrix renormalization group technique, to track current-carrying states of interacting fermions in one dimension and in presence of an Aharonov-Bohm magnetic flux. This protocol allows us to access highly excited states. We also discuss the connection with the entanglement entropy of these excited states.