Quantum coherence versus non-classical correlations in XXZ spin-chain under Dzyaloshinsky-Moriya (DM) and KSEA interactions

We address the dynamics of quantum coherence and non-classical correlations in a two-qubit one-dimensional XXZ Heisen-berg spin-1/2 chain when exposed to a homogeneous magnetic field and characterized by the combined effects of temperature, Dzyaloshinsky-Moriya (DM), Kaplan-Shekhtman-Entin-Wohlman-Aharony (KSEA) interactions. Using local quantum uncertainty, we estimate quantum correlations in the considered thermal state, whereas quantum coherence is measured using l(1) norm of coherence and relative entropy of coherence. We show that the qualitative as well as the quantitative features of the quantum correlations and coherence depend largely upon the parameters of the two-qubit spin-chain and magnetic field. Quantum correlations and coherence in spin chains have distinct natures and behave differently, which we find intriguing. The l(1) norm of coherence was shown to be more dependable than the relative entropy of coherence for quantifying coherence. The dynamical behavior of quantum correlations and coherence has been proven to be largely non-oscillatory. We further show that depending on the temperature, DM, and KSEA interaction strengths, not only can the coherence and non-classical correlations be preserved, but that the initial mixed states can be readily transformed into maximally correlated states.

Automated summary

We study the dynamics of quantum coherence and non-classical correlations in a two-qubit Heisenberg spin-1/2 chain, incorporating the effects of temperature, Dzyaloshinsky-Moriya (DM), and Kaplan-Shekhtman-Entin-Wohlman-Aharony (KSEA) interactions under a homogeneous magnetic field. Using local quantum uncertainty, we quantify quantum correlations in the thermal state, and measure quantum coherence using l(1) norm and relative entropy of coherence. Our results demonstrate that the nature and behavior of quantum correlations and coherence depend on the parameters of the spin chain and magnetic field. The l(1) norm is shown to provide a more reliable quantification of coherence compared to the relative entropy. We find that quantum correlations and coherence exhibit largely non-oscillatory dynamics. Additionally, depending on the temperature and interaction strengths, both coherence and non-classical correlations can be preserved, and initial mixed states can be transformed into maximally correlated states.