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arXiv · 2503.21573

Finite-temperature charge and spin transport in the one-dimensional Hubbard model accounting for its global [SU (2) X SU(2) X U(1)]/Z_2^2$ symmetry

J. M. P. Carmelo·J. E. C. Carmelo
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Abstract

Using a general representation that accounts for the effects on finite-temperature spin and charge transport of the global [SU (2) X SU(2) X U(1)]/(Z2 X Z2) symmetry of the one-dimensional (1D) Hubbard model, we show that important finite-temperature transport quantities as the finite-field spin and finite-chemical potential charge stiffnesses and the zero-field spin and zero-chemical potential charge diffusion constants are controlled by microscopic processes associated with the spin and charge elementary currents carried by the spin and charge carriers, respectively. We describe the model finite-temperature transport properties in terms of the microscopic processes associated with the spin and charge elementary currents carried by the corresponding carriers. We expect that the general representation used in our study is that suitable to address the open problems on finite-temperature transport in the 1D Hubbard model also discussed in this paper.

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J. M. P. Carmelo, J. E. C. Carmelo. 2025-03-27. Finite-temperature charge and spin transport in the one-dimensional Hubbard model accounting for its global [SU (2) X SU(2) X U(1)]/Z_2^2$ symmetry. https://doi.org/10.1103/physrevb.111.115157

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