Perturbation study of the conductance through a finite Hubbard chain

TL;DR

This paper investigates how the conductance of a finite Hubbard chain varies with coupling to reservoirs at zero temperature, revealing even-odd effects linked to Kondo and Mott-Hubbard physics using second-order perturbation theory.

Contribution

It provides a detailed analysis of conductance dependence on chain-reservoir coupling, extending previous work by exploring this aspect in the Hubbard model.

Findings

Conductance exhibits even-odd oscillations related to Kondo and Mott-Hubbard physics.

The coupling strength significantly influences the conductance behavior.

Second-order perturbation theory effectively captures the key transport properties.

Abstract

Transport through a Hubbard chain of size N (=1,2,3,...) connected to reservoirs is studied at T = 0 in an electron-hole symmetric case based on the second-order perturbation theory in U. The result shows a typical even-odd property corresponding to a Kondo or Mott-Hubbard physics. In this report, specifically, we study the dependence of the conductance on the coupling between the chain and reservoirs, which was not examined in detail in our previous report [Phy. Rev. B 59, 12240 (1999)].