Coupling of tunnel junctions by quantum circuit modes

Publisher Website
Google Scholar
Abstract
We study charge transport in two dc-biased normal tunnel junctions with ultralow capacitances that are built into separate, but capacitively coupled, circuits. Counterintuitively, the dc current through each of the junctions depends on the bias voltages of both junctions. This mutual influence comes about by the coupling of tunnel events to the ac modes of the curcuits. We derive a general formula for the additional current due to the coupling, and study the limiting cases of low and high lead impedance.