Current Correlations in a Quantum Dot Ring: A Role of Quantum Interference

Bogdan R. Bułka, Jakub Łuczak

Published 2019-04-30Version 1

We present studies of electron transport and circular currents, those induced by the bias voltage and the magnetic flux threaded a ring of three quantum dots coupled with two electrodes. Quantum interference of electron waves passing through the states with opposite chirality play a relevant role in transport, one can observe the Fano resonance with destructive interference. The quantum interference effect is quantitatively described by local bond currents and their correlation functions. Fluctuations of the transport current are characterized Lesovik's formula for the shot noise, which is a composition of the bond current correlation functions. In the presence of circular currents the cross-correlation of the bond currents can be very large, but it is negative and compensates large positive auto-correlation functions.