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Mean-Field Theory of a Quantum Heisenberg Spin Glass

Antoine Georges·Olivier Parcollet·Subir Sachdev
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Abstract

A full mean field solution of a quantum Heisenberg spin glass model is presented in a large-N limit. A spin glass transition is found for all values of the spin S. The quantum critical regime associated with the quantum transition at S=0, and the various regimes in the spin glass phase at high spin are analyzed. The specific heat is shown to vanish linearly with temperature. In the spin-glass phase, intriguing connections between the equilibrium properties of the quantum problem and the out-of-equilibrium dynamics of classical models are pointed out.

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Antoine Georges, Olivier Parcollet, Subir Sachdev. 1999-09-16. Mean-Field Theory of a Quantum Heisenberg Spin Glass. https://doi.org/10.1103/physrevlett.85.840

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