Tailoring Quantum Correlations of a Coupled Central Two Qubits Soaked in a Finite Temperature Antiferromagnetic Environment with Frequency Gap

Lukong Cornelius Fai¹, Ngwa Engelbert Afuoti^1,2, Georges Collince Fouokeng^1*, Jules Casimir Ngana Kuetche^1,3, Martin Tchoffo¹

¹Mesoscopic and Multilayer Structures Laboratory, Department of Physics, University of Dschang, Dschang, Cameroon.
²Department of Thermal Engineering and Energy, Douala University Institute of Technology, Douala, Cameroon.
³Department of Physics, University of Buea, Buea, Cameroon.

DOI: 10.4236/jqis.2014.44019                

Abstract

We revisit the quantum features of an anti-ferromagnetic (AF) spin environment at finite temperature with gap in its frequency spectrum, on the dynamics quantum correlations of a coupled central two qubits system with Dzyaloshinskii-Moriya (DM) interaction, prepared in two entangled Bell states. Using entanglement and quantum discord as quantum meters of decoherence, the prepared entangled states are classified as robust or fragile relative to the degree of information leakage to the AF environment. By tailoring the size of the frequency gap, anisotropy field strength and induced field, due to system AF spin environment coupling, size of the AF environment and DM interaction parameter, a decoherence-free sub-space can be accessed for efficient execution of quantum protocols encoded in the entangled states.

Keywords

Anti-Ferromagnetic Lattice, Anisotropy Field, Magnetic Field, Quantum Correlations, Central Two Qubits

Conflicts of Interest

The authors declare no conflicts of interest.

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