Moving a perturbation across quantum dots: tuning of Fano resonances

TL;DR

This paper introduces a method to tune Fano resonances in open quantum dots by moving a controllable perturbation, like an AFM tip, offering a magnetic-field-free way to manipulate quantum states.

Contribution

It demonstrates a novel approach to control Fano resonances through position-dependent perturbations, providing an alternative to traditional magnetic field methods.

Findings

Controllable perturbation can selectively manipulate quantum dot states.

Fano resonances can be tuned without magnetic fields.

Position control offers a feasible tuning mechanism.

Abstract

We propose a controllable way of tuning Fano resonances in open quantum dots in the absence of magnetic field. A quantum dot can be modified by changing the gate voltages that define the dot itself. An extra degree of freedom can be introduced by means of a controllable repulsive perturbation, such as the one induced by scanning a Atomic Force Microscope tip on a real sample. We numerically investigate the coupling between localized states in the dot and the continuum in the leads. The advantage of such position controllable perturbation is the selective manipulation of the quantum dot states. We show that this could be a feasible alternative to quantum dots in Aharonov-Bohm interferometers as a Fano resonance tuning device.