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Journal of Modern Optics

Correlations in a chain of three oscillators with nearest neighbour coupling

Bahari Idrus, A. Konstadopoulou, Timothy P. Spiller, Apostol Vourdas

Published Apr 10, 2010• 5 citations
Publisher

Abstract

A chain of three oscillators A, B, C with nearest neighbour coupling, is considered. It is shown that the correlations between A, C (which are not coupled directly) can be stronger than the correlations between A, B. Also in some cases various witnesses of entanglement show that A, C are entangled but they cannot lead to any conclusion about A, B.

DOI
10.1080/09500341003789926

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Entanglement in the Mixed-three-spin XXXXXXXXX Heisenberg Model with the Next-nearest-neighbour Interaction
In this paper, we investigate thermal pairwise quantum correlation for any pair of spins of a mixed-three-spin XXX Heisenberg system (with spins connected together with the nearest-neighbour (NN) and that of the next-nearest-neighbour (NNN) coupling constants J 1 and J 2 ) by means of concurrence and quantum discord, as functions of temperature T , magnetic field B and the coupling constants J 2 and J 1 .Some comparisons between these measures of entanglement are done for next-nearest-neighbour spins.We also express some magnetic properties and discuss the behaviour of the system in some special critical points.Some interesting and novel discussions are done to introduce some entanglement witnesses.