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Thermal conductivity of anisotropic and frustrated spin-1/2 chains

F. Heidrich-Meisner·A. Honecker·D. C. Cabra·W. Brenig
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Abstract

We analyze the thermal conductivity of anisotropic and frustrated spin-1/2 chains using analytical and numerical techniques. This includes mean-field theory based on the Jordan-Wigner transformation, bosonization, and exact diagonalization of systems with N<=18 sites. We present results for the temperature dependence of the zero-frequency weight of the conductivity for several values of the anisotropy Δ. In the gapless regime, we show that the mean-field theory compares well to known results and that the low-temperature limit is correctly described by bosonization. In the antiferromagnetic and ferromagnetic gapped regime, we analyze the temperature dependence of the thermal conductivity numerically. The convergence of the finite-size data is remarkably good in the ferromagnetic case. Finally, we apply our numerical method and mean-field theory to the frustrated chain where we find a good agreement of these two approaches on finite systems. Our numerical data do not yield evidence for a diverging thermal conductivity in the thermodynamic limit in case of the antiferromagnetic gapped regime of the frustrated chain.

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F. Heidrich-Meisner, A. Honecker, D. C. Cabra, W. Brenig. 2002-11-19. Thermal conductivity of anisotropic and frustrated spin-1/2 chains. https://doi.org/10.1103/physrevb.66.140406

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