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arXiv · 1110.0325

Parametrization of spin-1 classical states

Olivier Giraud·Petr Braun·Daniel Braun
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Abstract

We give an explicit parametrization of the set of mixed quantum states and of the set of mixed classical states for a spin--1. Classical states are defined as states with a positive Glauber-Sudarshan P-function. They are at the same time the separable symmetric states of two qubits. We explore the geometry of this set, and show that its boundary consists of a two-parameter family of ellipsoids. The boundary does not contain any facets, but includes straight-lines corresponding to mixtures of pure classical states.

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Olivier Giraud, Petr Braun, Daniel Braun. 2011-10-03. Parametrization of spin-1 classical states. https://doi.org/10.1103/physreva.85.032101

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