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Exact results for spatial decay of correlations in low-dimensional insulators II

Janusz Jedrzejewski·Taras Krokhmalskii
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Abstract

We study decay rates of one-body reduced density matrices in insulators, described by a tight-binding model, where not only an external potential but also hoppings are spatially modulated. We determine analytically the power in the power law and the correlation length in D=1 case and in several lattice directions in D=2 case. Unlike the uniform hopping case, in D=1 system and in some directions of D=2 system the correlation length is not determined uniquely by the gap. Moreover, a crossover from D=2-decay rates to D=1 ones is investigated.

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Janusz Jedrzejewski, Taras Krokhmalskii. 2005-10-05. Exact results for spatial decay of correlations in low-dimensional insulators II. https://doi.org/10.1103/physrevb.72.233106

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