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Journal of the Physical Society of Japan

Dynamics of Geometric Measure of Quantum Discord of Two Qubits in Independent Reservoirs

Longjiang Liu, Jiang Zhang, Song Cheng, D. M. Tong

Published May 20, 2013• 1 citation
Publisher

Abstract

We study the dynamics of geometric measure of quantum discord. The model under consideration is a physical system of two qubits coupled with two independent bosonic reservoirs described by Ohmic-like spectral densities. We aim to find how the system's geometric measure of quantum discord evolves, and whether and in what conditions it may remain constant for a time interval or be frozen forever. Our result shows that by properly choosing the system's initial states, geometric measure of quantum discord may hold a frozen phenomenon in a time interval for all the three types of reservoirs, sub-Ohmic, Ohmic, and super-Ohmic reservoirs, and it may also hold a time-invariant phenomenon for super-Ohmic reservoirs. The conditions satisfied by the coefficients of standard Bell-diagonal states, in which the frozen phenomenon in a time interval or the time-invariant phenomenon of geometric measure of quantum discord appears, are given.

DOI
10.7566/jpsj.82.064002

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