Chinese Physics Letters

Effects of Dzyaloshinskii—Moriya Interaction on Optimal Dense Coding Using a Two-Qubit Heisenberg XXZ Chain with and without External Magnetic Field

Jiangtao Cai, Ahmad Abliz, Yan-Kui Bai, Guang-Sheng Jin

Published Feb 1, 2011• 4 citations

Abstract

We investigate the effects of different components of the Dzyaloshinskii—Moriya (DM) anisotropic antisymmetric interaction on optimal dense coding with a two-qubit Heisenberg XXZ chain in the presence and in the absence of external magnetic fields. The anisotropic coupling parameter Δ, isotropic coupling parameter J , and the DM interaction parameters are found to be effective for optimal dense coding, while the magnetic field turns out to be destructive. Moreover, the results show that the case of antiferromagnetic (AFM) is more ideal for optimal dense coding than the case of ferromagnetic (FM) in general. In the case of AFM, by comparison of the two cases with the same fixed x - and z -component parameters of DM interaction ( D x and D z ), the appropriate model for optimal dense coding is indicated for the different value intervals of Δ. Comparison of the effects of D z and D x on optimal dense coding is made and their dominant regions are clarified.

DOI: 10.1088/0256-307x/28/2/020307

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