Measuring entanglement using quantum quenches

TL;DR

This paper proposes a method to measure entanglement in one-dimensional quantum systems near critical points by analyzing energy level populations after a local quench.

Contribution

It introduces a novel approach linking entanglement entropy measurement to quantum quenches and energy level analysis.

Findings

Entanglement can be inferred from low-lying energy level populations.

The method applies to systems near quantum critical points.

Potential experimental implementation for entanglement measurement.

Abstract

We show that block entanglement entropies in one-dimensional systems close to a quantum critical point can in principle be measured in terms of the population of low-lying energy levels following a certain type of local quantum quench.