arXiv:cond-mat/0301253 · Physical Review Letters
Drude Weight at Finite Temperatures for Some Nonintegrable Quantum Systems in One Dimension
Satoshi Fujimoto, Norio Kawakami
Abstract
Using conformal perturbation theory, we show that, for some classes of the one-dimensional quantum liquids that possess the Luttinger liquid fixed point in the low-energy limit, the Drude weight at finite temperatures is nonvanishing, even when the system is nonintegrable and the total current is not conserved. We also obtain the asymptotically exact low-temperature formula of the Drude weight for Heisenberg XXZ spin chains, which agrees quite well with recent numerical data.