Hamiltonian approach to the ac Josephson effect in superconducting-normal hybrid systems
Abstract
The ac Josephson effect in hybrid systems of a normal mesoscopic conductor coupled to two superconducting (S) leads is investigated theoretically. A general formula of the ac components of time-dependent current is derived which is valid for arbitrary interactions in the normal region. We apply this formula to analyze a S-normal-S system where the normal region is a noninteracting single level quantum dot. We report the physical behavior of time-averaged nonequilibrium distribution of electrons in the quantum dot, the formation of Andreev bound states, and ac components of the time-dependent current. The distribution is found to exhibit a population inversion; and all Andreev bound states between the superconducting gap carry the same amount of current and in the same flow direction. The ac components of time-dependent current show strong oscillatory behavior in marked contrast to the subharmonic gap structure of the average current.
Keywords
Cite
@article{arxiv.cond-mat/0108164,
title = {Hamiltonian approach to the ac Josephson effect in superconducting-normal hybrid systems},
author = {Qing-feng Sun and Hong Guo and Jian Wang},
journal= {arXiv preprint arXiv:cond-mat/0108164},
year = {2009}
}
Comments
23 pages, 10 figures, LaTex