Transport in a classical model of a one-dimensional Mott insulator: Influence of conservation laws
Institut für Theorie der Kondensierten
Materie, Universität Karlsruhe D-76128 Karlsruhe, Germany
Accepted: 17 April 2001
We study numerically how conservation laws affect the optical conductivity of a slightly doped one-dimensional Mott insulator. We investigate a regime where the average distance between charge excitations is large compared to their thermal de Broglie wavelength and a classical description is possible. Due to conservation laws, the dc conductivity is infinite and the Drude weight D is finite even at finite temperatures. Our numerical results test and confirm exact theoretical predictions for D both for integrable and non-integrable models. Small deviations from integrability induce slowly decaying modes and, consequently, low-frequency peaks in , which can be described by a memory matrix approach.
PACS: 72.20.-i – Conductivity phenomena in semiconductors and insulators / 71.10.Pm – Fermions in reduced dimensions (anyons, composite fermions, Luttinger liquid, etc.) / 72.15.Nj – Collective modes (e.g., in one-dimensional conductors)
© EDP Sciences, 2001