Transport in multi-chain models of interacting fermions

Abstract

We study transport in a class of exactly solvable multi-chain models of interacting fermions using bosonization. We introduce magnetic and non-magnetic impurities at a site, through either weak δ-function potentials or weak links. Using a renormalization group analysis, we show that the strength of the non-magnetic impurity is not affected by the interaction and hence, conductance through the impurity can be exactly computed. Magnetic impurities, on the other hand, in a single- or two-chain model always cut the wire at the impurity site. However, when the number of chains is greater than two, we find a critical interaction strength beyond which there exists a metal-insulator transition tuned by the strength of the magnetic impurity.