Decoherence of two qubits coupled to an XY spin chain at finite temperature with the Dzyaloshinsky–Moriya interaction

Abstract

The entanglement dynamics between two central spins coupled to an XY spin chain at finite temperature with the Dzyaloshinsky–Moriya interaction (DM) is investigated. By studying the entanglement decay of the central spins, we find that the DM interaction does not affect the behaviour of quantum phase transition induced by the external magnetic field and does not induce new critical regions in the XY model. Moreover, the DM interaction can efficiently enhance or suppress the entanglement between the central spins which depend on the values of the DM interaction, the magnetic intensity λ and the temperature T of the environmental spin chain.