Numerical Studies of Fano Resonance in Quantum dots Embedded in AB Rings

TL;DR

This paper theoretically investigates Fano resonance in quantum dots within Aharonov-Bohm rings, deriving analytical conductance expressions and exploring flux-dependent resonance shapes and dephasing effects, aligning with recent experiments.

Contribution

It provides an analytical model for Fano resonance in quantum dots embedded in AB rings and examines flux-induced resonance shape changes and dephasing effects.

Findings

Conductance expressed in an extended Fano form with complex parameters.

Resonance shape varies from symmetric to asymmetric with magnetic flux.

Dephasing effects influence the Fano resonance profile.

Abstract

The Fano resonance in quantum dots embedded in Aharonov-Bohm rings is examined theoretically, using two models of non-interacting electrons. The first model yields an analytical expression for the conductance G. G is written in an extended Fano form with a complex parameter. The shape of the resonance can be asymmetric or symmetric, depending on the magnetic flux enclosed in the ring. The "phase" of the resonance is changed continuously with increasing the flux in two-terminal situations. These are in accordance with recent experimental results. In the second model, we consider the dephasing effect on the Fano resonance by numerical calculations.