Coupled Landau-Zener-Stuckelberg Quantum Dot Interferometers

TL;DR

This paper explores how phase differences in ac voltages applied to a triple quantum dot system can control photon-assisted transport, revealing interference effects like dark states and quantum destructive interference.

Contribution

It introduces a method to manipulate quantum interference in triple quantum dots via phase tuning of external ac voltages, highlighting new control mechanisms.

Findings

Phase opposition leads to quantum destructive interference.

In-phase voltages create dark states that cancel current.

Interference effects are experimentally observable.

Abstract

We investigate the interplay between long-range and direct photon-assisted transport in a triple quantum dot chain where local ac voltages are applied to the outer dots. We propose the phase difference between the two ac voltages as an external parameter, which can be easily tuned to manipulate the current characteristics. For gate voltages in phase opposition we find quantum destructive interferences analogous to the interferences in closed-loop undriven triple dots. As the voltages oscillate in phase, interferences between multiple paths give rise to dark states. Those totally cancel the current, and could be experimentally resolved.