arXiv:1209.4166 · Journal of Physics A Mathematical and Theoretical

Quantum correlations in a system of nuclears= 1/2 spins in a strong magnetic field

Edward B. Fel’dman, E. I. Kuznetsova, M. A. Yurishchev

Published Nov 8, 2012• 25 citations

Abstract

Entanglement and quantum discord for a pair of nuclear spins s = 1/2 in a nanopore filled with a gas of spin-carrying molecules (atoms) are studied. The correlation functions describing dynamics of dipolar-coupled spins in a nanopore are found. The dependence of spin-pair entanglement on the temperature and the number of spins is obtained from the reduced density matrix, which is centrosymmetric (CS). An analytic expression for the concurrence is obtained for an arbitrary CS density matrix. It is shown that the quantum discord as a measure of quantum correlations attains a significant value at low temperatures. It is also shown that the discord in the considered model has 'flickering' character and disappears periodically in the course of time evolution of the system. The geometric discord is studied for arbitrary 4 × 4 CS density matrices.

DOI: 10.1088/1751-8113/45/47/475304

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