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Journal of the Physical Society of Japan

Ground State of Quantum Spin Glass with Infinite Range Interactions

Hidetoshi Nishimori, Y‐h. Taguchi, Takehiko Oguchi

Published Feb 15, 1986• 5 citations
Publisher

Abstract

We have investigated the spin-1/2 random Heisenberg model with infinite range interactions by a numerical method. Extrapolation of finite size ( N ≦16) properties to the infinite system has yielded the following results. The average ground state energy is lower than that of the SK model (Ising spin) by about 25%. In the ground state, a critical point between the spin glass and ferromagnetic (mixed) phases exists just around the critical point (\(\tilde{J}_{0}/\tilde{J}{=}1\)) of the corresponding classical random Heisenberg model. Quantum fluctuations are concluded not to change the ground state properties qualitatively.

DOI
10.1143/jpsj.55.656

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