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Entanglement Induced Phase Transitions

Dorje C. Brody·Lane P. Hughston·Matthew F. Parry
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Abstract

Starting from the canonical ensemble over the space of pure quantum states, we obtain an integral representation for the partition function. This is used to calculate the magnetisation of a system of N spin-1/2 particles. The results suggest the existence of a new type of first order phase transition that occurs at zero temperature in the absence of spin-spin interactions. The transition arises as a consequence of quantum entanglement. The effects of internal interactions are analysed and the behaviour of the magnetic susceptibility for a small number of interacting spins is determined.

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Dorje C. Brody, Lane P. Hughston, Matthew F. Parry. 2001-03-28. Entanglement Induced Phase Transitions. https://doi.org/10.1016/j.physleta.2010.03.060

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