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.