English

Local quantum Fisher information and local quantum uncertainty for general X-states

Quantum Physics 2023-05-16 v1 Statistical Mechanics

Abstract

A two-spin-1/2 Heisenberg XYZ model with Dzyaloshinsky--Moriya (DM) and Kaplan--Shekhtman--Entin-Wohlman--Aharony (KSEA) interactions in the presence of an inhomogeneous external magnetic field is considered at thermal equilibrium. Its density matrix has the general X form for which we derive explicit formulas for the local quantum Fisher information (LQFI) and local quantum uncertainty (LQU) directly in terms of model parameters. This allows us to perform a comparative study for the discord-type quantum correlations LQFI and LQU and to reveal a number of new features in their behavior. In particular, the sudden transitions of quantum correlations with a smooth change in temperature are found. Moreover, it is shown that there may be a sequence of such transitions for certain choices of interaction constants.

Keywords

Cite

@article{arxiv.2303.03685,
  title  = {Local quantum Fisher information and local quantum uncertainty for general X-states},
  author = {M. A. Yurischev and Saeed Haddadi},
  journal= {arXiv preprint arXiv:2303.03685},
  year   = {2023}
}

Comments

17 pages, 4 figures (7 eps files)