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Critical Properties of Spectral Functions for the 1D Anisotropic t-J Models with an Energy Gap

T. Fujii·Y. Tsukamoto·N. Kawakami
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Abstract

We exactly calculate the momentum-dependent critical exponents for spectral functions in the one-dimensional anisotropic t-J models with a gap either in the spin or charge excitation spectrum. Our approach is based on the Bethe ansatz technique combined with finite-size scaling techniques in conformal field theory. It is found that the spectral functions show a power-law singularity, which occurs at frequencies determined by the dispersion of a massive spin (or charge) excitation.We discuss how the nontrivial contribution of a massive excitation controls the singular behavior in optical response functions.

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T. Fujii, Y. Tsukamoto, N. Kawakami. 1997-10-22. Critical Properties of Spectral Functions for the 1D Anisotropic t-J Models with an Energy Gap. https://doi.org/10.1143/jpsj.66.2552

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