Enhancing the Detection of Natural Thermal Entanglement with Disorder

TL;DR

This paper explores how disorder in physical systems can enhance the detection of natural thermal entanglement, using perturbation theory to analyze random spin chains.

Contribution

It introduces a method applying many-body perturbation theory to account for disorder in thermal entanglement detection, demonstrating enhancement in a spin chain model.

Findings

Disorder can increase the detectable region of thermal entanglement.

Perturbation theory enables analysis of quenched and annealed averages.

Random coupling strengths can enhance entanglement detection.

Abstract

Physical systems have some degree of disorder present in them. We discuss how to treat natural, thermal entanglement in any random macroscopic system from which a thermodynamic witness bounded by a constant can be found. We propose that functional many-body perturbation theory be applied to allow either a quenched or an annealed average over the disorder to be taken. We find when considering the example of an XX Heisenberg spin chain with a random coupling strength, that the region of natural entanglement detected by both witnesses can be enhanced by the disorder.