h/2eOscillations for Correlated Electron Pairs in Disordered Mesoscopic Rings

Abstract

The full spectrum of two interacting electrons in a disordered mesoscopic one-dimensional ring threaded by a magnetic flux is calculated numerically. For ring sizes far exceeding the one-particle localization length $L_1$ we find $h/2e$-periodic energy levels whose eigenfunctions exhibit a pairing effect. This represents the first direct observation of interaction-assisted coherent pair propagation. Shape and number of the pair states are consistent with our previous transfer matrix study.