Antiresonance and bound states in the continuum in electron transport through parallel-coupled quantum-dot structures.

Abstract

In this paper we make a theoretical study of electron transport through a multi-quantum-dot system, in which the peripheral quantum dots of a one-dimensional chain are embodied in the two arms of an Aharonov-Bohm interferometer. It is found that, in the absence of magnetic flux, all the even molecule states of odd-numbered quantum-dot structures decouple from the leads and in even-numbered quantum-dot systems all the odd molecule states decouple from the leads, which indicates the formation of remarkable bound states in the continuum. Meanwhile, what is interesting is that apparent antiresonance occurs in electron transport through this structure, the positions of which are accordant with all even (odd) eigenenergies of the sub-molecule of the even (odd)-numbered quantum dots without the peripheral dots. All these results are efficiently modified by the presence of magnetic flux through this system.