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arXiv · 1504.02030

Quasiprobability distributions in open quantum systems: spin-qubit systems

Kishore Thapliyal·Subhashish Banerjee·Anirban Pathak·S. Omkar·V. Ravishankar
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Abstract

Quasiprobability distributions (QDs) in open quantum systems are investigated for $SU(2)$, spin like systems, having relevance to quantum optics and information. In this work, effect of both quantum non-demolition (QND) and dissipative open quantum systems, on the evolution of a number of spin QDs are investigated. Specifically, compact analytic expressions for the $W$, $P$, $Q$, and $F$ functions are obtained for some interesting single, two and three qubit states, undergoing general open system evolutions. Further, corresponding QDs are reported for an N qubit Dicke model and a spin-1 system. The existence of nonclassical characteristics are observed in all the systems investigated here. The study leads to a clear understanding of quantum to classical transition in a host of realistic physical scenarios. Variation of the amount of nonclassicality observed in the quantum systems, studied here,are also investigated using nonclassical volume.

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Kishore Thapliyal, Subhashish Banerjee, Anirban Pathak, S. Omkar, V. Ravishankar. 2015-04-08. Quasiprobability distributions in open quantum systems: spin-qubit systems. https://doi.org/10.1016/j.aop.2015.07.029

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