Transport through two interacting resonant levels connected by a Fermi sea
Abstract
We study transport at finite bias, i.e. beyond the linear regime, through two interacting resonant levels connected by a Fermi sea, by means of time-dependent density matrix renormalization group. We first consider methodological issues, like the protocol that leads to a current-currying state and the characterization of the steady state. At finite sizes both the current and the occupations of the interacting levels oscillate as a function of time. We determine the amplitude and period of such oscillations as a function of bias. We find that the occupations on the two dots oscillate with a relative phase which depends on the distance between the impurities and on the Fermi momentum of the Fermi sea, as expected for RKKY interactions. Also the approximant to the steady-state current displays oscillations as a function of the distance between the impurities. Such a behavior can be explained by resonances in the free case. We then discuss the incidence of interaction on such a behavior. We conclude by showing the effect of the bias on the current, making connection with the one-impurity case.
Keywords
Cite
@article{arxiv.1301.7683,
title = {Transport through two interacting resonant levels connected by a Fermi sea},
author = {Elena Canovi and Alexander Moreno and Alejandro Muramatsu},
journal= {arXiv preprint arXiv:1301.7683},
year = {2013}
}
Comments
11 pages, 17 figures, revised version, accepted for publication in Phys. Rev. B