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arXiv · 1712.07634

Analysis of quantum phase transition in some different Curie-Weiss models: a unified approach

Carla Maria Pontes Carneiro·Giancarlo Queiroz Pellegrino
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Abstract

A unified approach to the analysis of quantum phase transitions in some different Curie-Weiss models is proposed such that they are treated and analyzed under the same general scheme. This approach takes three steps: balancing the quantum Hamiltonian by an appropriate factor, rewriting the Hamiltonian in terms of $SU(2)$ operators only, and obtention of a classical Hamiltonian. $SU(2)$ operators are obtained from creation and annihilation operators as linear combinations in the case of fermions and as an inverse Holstein-Primakoff transformation in the case of bosons. This scheme is successfully applied to Lipkin, pairing, Jaynes-Cummings, bilayer, and Heisenberg models.

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Carla Maria Pontes Carneiro, Giancarlo Queiroz Pellegrino. 2017-12-20. Analysis of quantum phase transition in some different Curie-Weiss models: a unified approach. https://arxiv.org/abs/1712.07634

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