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arXiv · 1904.07643

Allowed and Forbidden Bipartite Correlations from Thermal States

Tamal Guha·Mir Alimuddin·Preeti Parashar
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Abstract

The strong connection between correlations and quantum thermodynamics raises a natural question about the preparation of correlated quantum states from two copies of a thermal qubit. In this work we study the specific forms of allowed and forbidden bipartite correlations. As a consequence, we extend the result to Separable (SEP) but not Absolutely Separable (AbSEP) class of product states. Preparation of a general form of entanglement from arbitrary thermal qubits is studied and as an application we propose a strategy to establish sustained entanglement between two distant parties. The threshold temperature to produce entanglement from two copies of a thermal qubit has also been discussed from the resource theoretic perspective, which ensures that the bound on the temperature can be superseded with the help of a resource state. A dimension dependent upper-bound on the temperature is derived, below which two copies of any d-dimensional thermal state can be entangled in 2xd dimension.

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Tamal Guha, Mir Alimuddin, Preeti Parashar. 2019-04-16. Allowed and Forbidden Bipartite Correlations from Thermal States. https://doi.org/10.1103/physreve.100.012147

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