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arXiv · 0802.0278

Stable Mean Field Solution of a Short-Range Interacting SO(3) Quantum Heisenberg Spin-Glass

C. M. S. da Conceição·E. C. Marino
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Abstract

We present a mean-field solution for a quantum, short-range interacting, disordered, SO(3) Heisenberg spin model, in which the Gaussian distribution of couplings is centered in an AF coupling $\bar J>0$, and which, for weak disorder, can be treated as a perturbation of the pure AF Heisenberg system. The phase diagram contains, apart from a Néel phase at T=0, spin-glass and paramagnetic phases whose thermodynamic stability is demonstrated by an analysis of the Hessian matrix of the free-energy. The magnetic susceptibilities exhibit the typical cusp of a spin-glass transition.

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C. M. S. da Conceição, E. C. Marino. 2008-02-03. Stable Mean Field Solution of a Short-Range Interacting SO(3) Quantum Heisenberg Spin-Glass. https://doi.org/10.1103/physrevlett.101.037201

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