Highly Tunable Hybrid Quantum Dots with Charge Detection

TL;DR

This paper presents a hybrid quantum dot device with tunable confinement and sensitive charge detection, achieved through combining local anodic oxidation and Schottky-gates, enabling precise control of single-electron states.

Contribution

It introduces a novel hybrid quantum dot device with integrated charge detection, demonstrating high tunability and control over electron occupancy and tunnel couplings.

Findings

Quantum dot with single-electron control

Charge detector signal observed across various tunnel couplings

Device demonstrates high tunability and control

Abstract

In order to employ solid state quantum dots as qubits, both a high degree of control over the confinement potential as well as sensitive charge detection are essential. We demonstrate that by combining local anodic oxidation with local Schottky-gates, these criteria are nicely fulfilled in the resulting hybrid device. To this end, a quantum dot with adjacent charge detector is defined. After tuning the quantum dot to contain only a single electron, we are able to observe the charge detector signal of the quantum dot state for a wide range of tunnel couplings.