Eur. Phys. J. B (2018) 91: 238
https://doi.org/10.1140/epjb/e2018-90027-7

Regular Article

Time-dependent transport through a T-coupled quantum dot

¹ Department of Physics, National and Kapodistrian University of Athens, 15771 Athens, Greece
² LUNAM Université, Université du Maine, CNRS, LAUM UMR 6613, Av. O. Messiaen, 72085 Le Mans, France

^a e-mail: gepavlou@phys.uoa.gr

Received: 17 January 2018
Received in final form: 23 May 2018
Published online: 8 October 2018

Abstract

We are considering the time-dependent transport through a discrete system, consisting of a quantum dot T-coupled to an infinite tight-binding chain. The periodic driving that is induced on the coupling between the dot and the chain, leads to the emergence of a characteristic multiple Fano resonant profile in the transmission spectrum. We focus on investigating the underlying physical mechanisms that give rise to the quantum resonances. To this end, we use Floquet theory for calculating the transmission spectrum and in addition employ the Geometric phase propagator approach [G. Pavlou, A. Karanikas, F. Diakonos, Ann. Phys. 375, 351 (2016)] to calculate the transition amplitudes of the time-resolved virtual processes, in terms of which we describe the resonant behavior. This two fold approach, allows us to give a rigorous definition of a quantum resonance in the context of driven systems and explains the emergence of the characteristic Fano profile in the transmission spectrum.