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Quantum and thermal fluctuations in the SU(N) Heisenberg spin-glass model near the quantum critical point

A. Camjayi·M. J. Rozenberg
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Abstract

We solve for the SU(N) Heisenberg spin-glass in the limit of large N focusing on small S and T. We study the effect of quantum and thermal fluctuations in the frequency dependent response function and observed interesting transfers of spectral weight. We compute the T-dependence of the order parameter and the specific heat and find an unusual T^2 behavior for the latter at low temperatures in the spin-glass phase. We find a remarkable qualitative agreement with various experiments on the quantum frustrated magnet SrCr_{9p}Ga_{12-9p}O_{19}.

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A. Camjayi, M. J. Rozenberg. 2002-10-18. Quantum and thermal fluctuations in the SU(N) Heisenberg spin-glass model near the quantum critical point. https://doi.org/10.1103/physrevlett.90.217202

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