Behavior of quantum discord, local quantum uncertainty, and local quantum Fisher information in two-spin-1/2 Heisenberg chain with DM and KSEA interactions

TL;DR

This paper analyzes quantum correlations in a two-spin-1/2 Heisenberg chain with DM and KSEA interactions, deriving formulas for quantum measures and comparing their behavior across parameters and temperature.

Contribution

It provides analytical formulas for LQU and LQFI in a Heisenberg model with DM and KSEA interactions and compares these with quantum discord.

Findings

Quantum correlations show similar behavior across measures with temperature changes.

Regions exist where correlations increase with temperature.

Sudden changes in correlations occur at specific interaction parameters.

Abstract

A two-qubit Heisenberg XYZ model with Dzyaloshinsky-Moriya (DM) and Kaplan-Shekhtman-Entin-Wohlman--Aharony (KSEA) interactions is considered at thermal equilibrium. Analytical formulas are derived for the local quantum uncertainty (LQU) and local quantum Fisher information (LQFI). Using the available expressions for the entropic quantum discord, we perform a comparative study of these measures of nonclassical correlation. Our analysis showed the following: all three measures of quantum correlation have similar qualitative and even quantitative behavior on temperature for different values of system parameters, there are regions in the parameter space which correspondent to a local increase of correlations with increasing temperature, and sudden changes in the behavior of quantum correlations occur at certain values of the interaction parameters.