Phase transitions and entanglement properties in spin-1 Heisenberg clusters with single-ion anisotropy

TL;DR

This paper investigates quantum phase transitions and entanglement in spin-1 Heisenberg clusters with anisotropy, revealing how microscopic entanglement relates to critical points and phase behavior using exact diagonalization.

Contribution

It introduces a detailed analysis of entanglement and phase transitions in anisotropic spin-1 Heisenberg clusters with single-ion anisotropy and magnetic field, using negativity as a measure.

Findings

Quantum critical points are linked to changes in magnetization and entanglement.

Susceptibility peaks indicate different entangled phases and ordered states.

Exact diagonalization reveals the relationship between microscopic entanglement and collective excitations.

Abstract

The incipient quantum phase transitions of relevance to nonzero fluctuations and entanglement in Heisenberg clusters are studied in this paper by exploiting negativity as a measure in bipartite and frustrated spin-1 anisotropic Heisenberg clusters with bilinear-biquadratic exchange, single-ion anisotropy and magnetic field. Using the exact diagonalization technique, it is shown that quantum critical points signaled by qualitative changes in behavior of magnetization and particle number are ultimately related to microscopic entanglement and collective excitations. The plateaus and peaks in spin and particle susceptibilities define the conditions for a high/low-density quantum entanglement and various ordered phases with different spin (particle) concentrations.