Document DOI: 10.1209/epl/i2002-00328-9
Europhys. Lett., 60 (1) , pp. 120-126 (2002)
Disorder-induced enhancement of the persistent current for strongly interacting electrons in one-dimensional rings
E. Gambetti-Césare1, D. Weinmann1, R. A. Jalabert1, 2 and Ph. Brune31 Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 (CNRS-ULP) 23 rue du Loess, 67037 Strasbourg Cedex, France
2 Institute for Theoretical Physics, University of California Santa Barbara, CA 93106, USA
3 Institut für Physik, Universität Augsburg - 86135 Augsburg, Germany
weinmann@ipcms.u-strasbg.fr
(Received 11 April 2002; accepted in final form 15 July 2002)
Abstract
We show that disorder increases the persistent current of
a half-filled one-dimensional Hubbard-Anderson ring at strong interaction.
This unexpected effect results from a perturbative expansion starting
from the strongly interacting Mott insulator ground state.
The analytical result is confirmed and extended by numerical
calculations.
73.23.Ra - Persistent currents.
71.10.Fd - Lattice fermion models (Hubbard model, etc.).
© EDP Sciences 2002