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

## TL;DR

This paper investigates electron transport and quantum interference effects in a three-quantum-dot ring, revealing how magnetic flux and bias influence circular currents, Fano resonances, and current fluctuations.

## Contribution

It provides a quantitative analysis of quantum interference effects on transport and current correlations in a quantum dot ring, highlighting the role of bond current correlations.

## Key findings

- Quantum interference significantly affects electron transport.
- Fano resonance with destructive interference observed.
- Large negative cross-correlations counterbalance positive auto-correlations.

## Abstract

We present studies of the electron transport and circular currents induced by the bias voltage and the magnetic flux threading a ring of three quantum dots coupled with two electrodes. Quantum interference of electron waves passing through the states with opposite chirality plays a relevant role in transport, where one can observe 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 by the Lesovik 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 for the large positive auto-correlation functions.