International Journal of Theoretical Physics

, Volume 55, Issue 4, pp 2089–2096 | Cite as

Decoherence of Two-qubits Coupled with Reservoirs Studied with New Ket-Bra Entangled State Method



For the first time we define a so-called Ket-Bra Entangled State (KBES) for two-qubits coupled with reservoirs by introduce an extra fictitious mode vector, and convert the corresponding master equation into Schrödinger-like equation by virtue of this state. Via this approach we concisely obtain the dynamic evolution of two uncoupled qubits each immersed in local thermal noise. Based on this, the decoherence evolution for the extended Werner-like states is derived and how purity and temperature influence the concurrence is analyzed. This KBES method may also be applied to tackling master equations of limited atomic level systems.


Ket-Bra entangled state Schrödinger-like equation Master equation Decoherence and concurrence 


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© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.University of Science and Technology of ChinaHefeiChina

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