Tuning Fano-type resonances in coupled quantum point contacts by applying asymmetric voltages

Rubén C. Villarreal, Francisco Mireles, Ernesto E. Marinero, Bruce A. Gurney
2011 Applied Physics Letters  
We study the ballistic magnetotransport in a double quantum point contact (QPC) device consisting of a quasi-one-dimensional quantum wire with an embedded island-like impurity - etched nano-hole as in a recently published experiment [J. C. Chen, Y. Lin, K.-T. Lin, T. Ueda and S. Komiyama, Appl. Phys. Lett. 94, 012105 (2009)]. We reproduce the zero field quantized conductance, the interference phenomenon induced by the coupled QPCs, as well as the Ramsauer-like resonances observed in the
more » ... nts. At finite magnetic fields Fano-type resonances arises in the conductance due to the formation of localized states at the impurity periphery and to an inter-edge state resonant coupling effect. It is predicted that the Fano-type resonances can be controlled by an asymmetric confinement of the QPCs.
doi:10.1063/1.3579538 fatcat:iobmw53tp5dk3oyctyh3zkrgfm