Quantum Fluctuations of a Nearly Critical Heisenberg Spin Glass I. Model and Outline of the Results
نویسنده
چکیده
T thermodynamics: we find a specific heat linear in T and a local spectral density of spin excitations, χ′′ loc(ω) ∼ ω for a spin glass state which is marginally stable to fluctuations in the replicon modes. For small S, the spin-glass order is fragile, and a spin-liquid state with χ′′ loc ∼ tanh(ω/2T) dominates the properties over a significant range of T and ω. We argue that the latter state may be relevant in understanding the properties of strongly-disordered
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Quantum Fluctuations of a Nearly Critical Heisenberg Spin Glass
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