From conformal to volume-law for the entanglement entropy in exponentially deformed critical spin 1/2 chains

TL;DR

This paper investigates how exponential deformation in 1D critical spin-1/2 chains transitions the entanglement entropy from a conformal to a volume-law, exemplified in XX and Heisenberg models, revealing a crossover in entanglement properties.

Contribution

It demonstrates the emergence of volume-law entanglement in deformed critical chains and characterizes the crossover between critical and maximally entangled states.

Findings

Exponential deformation induces volume-law entanglement entropy.

Crossover between critical and maximally entangled states characterized.

Analysis performed on XX and Heisenberg models.

Abstract

An exponential deformation of 1D critical Hamiltonians gives rise to ground states whose entanglement entropy satisfies a volume-law. This effect is exemplified in the XX and Heisenberg models. In the XX case we characterize the crossover between the critical and the maximally entangled ground state in terms of the entanglement entropy and the entanglement spectrum.