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arXiv · 1304.5918

Kraus representation for maps and master equation in spin star model with layered environment

Mahmoud Mahdian·Hadi Mehrabpour
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Abstract

Quantum operations are usually defined as completely positive (CP), trace preserving (TP) maps on quantum states, and can be represented by operator-sum or Kraus representations. In this paper, we calculate operator-sum representation and master equation of an exactly solvable dynamic of one-qubit open system in layered environment . On the other hand, we obtain exact Nakajima-Zwanzig (NZ) and time-convolutionless (TCL) master equation from the maps. Finally, we study a simple example to consider the relation between CP maps and initial quantum correlation and show that vanishing initial quantum correlation is not necessary for CP maps.

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Mahmoud Mahdian, Hadi Mehrabpour. 2013-04-22. Kraus representation for maps and master equation in spin star model with layered environment. https://arxiv.org/abs/1304.5918

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