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arXiv:1410.6988 · Progress of Theoretical and Experimental Physics

Entanglement entropies of non-equilibrium finite-spin systems

K. Nakagawa

Published Feb 6, 2015• 3 citations
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Abstract

For the purpose of clarifying a new approach to understanding quantum entanglement using thermofield dynamics (TFD), entanglement entropies of non-equilibrium finite-spin systems are examined for both traditional and extended cases. The extended entanglement entropy, |$\hat {S}$|⁠, is derived, and it is found that the conditions for the maximum entangled state can be obtained through this approach. The capacity of the TFD-based method to distinguish between states in quantum systems is confirmed.

DOI
10.1093/ptep/ptv005

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