Interplay between electrostatic and tunnel couplings in an independently contacted double quantum dot–quantum wire coupled device

We have studied low temperature transport characteristics of an independently contacted double quantum dot–quantum wire coupled system. Each quantum dot is connected to three leads; source, drain and wire. Fano resonances associated with one dot appear in the conductance of the other dot, which are gradually suppressed as the inter-dot tunnel coupling via the wire is reduced. When the dot-wire tunnel coupling is lost, conductance modulation similar to the Fano resonances reappear, which is ascribed to purely inter-dot electrostatic coupling effect.