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arXiv · 0710.4440

Role of symmetry in the interplay of T=0 quantum-phase transitions with unconventional T>0 transport properties in integrable quantum lattice systems

Jose. M. P. Carmelo·Shi-Jian. Gu·Nuno. M. R. Peres
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Abstract

We show that a generalized charge SU(2) symmetry of the one-dimensional (1D) Hubbard model in an infinitesimal flux $ϕ$ generates half-filling states from metallic states which lead to a finite charge stiffness $D(T)$ at finite temperature $T$, whose $T$ dependence we study. Our results are of general nature for many integrable quantum lattice systems, reveal the microscopic mechanisms behind their exotic $T>0$ transport properties and the interplay with T=0 quantum-phase transitions, and contribute to the further understanding of the transport of charge in systems of interacting ultracold fermionic atoms in 1D optical lattices, quasi-1D compounds, and 1D nanostructures.

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Jose. M. P. Carmelo, Shi-Jian. Gu, Nuno. M. R. Peres. 2007-10-24. Role of symmetry in the interplay of T=0 quantum-phase transitions with unconventional T>0 transport properties in integrable quantum lattice systems. https://doi.org/10.1209/0295-5075/78/17005

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