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

¹  GCEP-Center of Physics, U. Minho, Campus Gualtar - P-4710-057 Braga, Portugal
²  Massachusetts Institute of Technology - Cambridge, MA 02139-4307, USA
³  Department of Physics and ITP, The Chinese University of Hong Kong - Hong Kong, China

Corresponding author: carmelo@fisica.uminho.pt

Received: 2 October 2006
Accepted: 13 February 2007

Abstract

We show that a generalized charge symmetry of the one-dimensional (1D) Hubbard model in an infinitesimal flux generates half-filling states from metallic states which lead to a finite charge stiffness 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 transport properties and the interplay with 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.