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تسجيل مستخدم جديدFinite temperature transport in disordered Heisenberg chains
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Using numerical diagonalization techniques, we explore the effect of local and bond disorder on the finite temperature spin and thermal conductivities of the one dimensional anisotropic spin-1/2 Heisenberg model. High-temperature results for local disorder show that the dc conductivties are finite, apart from the uncorrelated - XY case - where dc transport vanishes. Moreover, at strong disorder, we find finite dc conductivities at all temperatures $T$, except T=0. The low frequency conductivities are characterized by a nonanalytic cusp shape. Similar behavior is found for bond disorder.
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