Charge-Tunable Indium Gallium Nitride Quantum Dots

TL;DR

This paper demonstrates quantized single-electron charging in site-controlled III-Nitride quantum dots, advancing their potential for quantum information processing and spintronics at non-cryogenic temperatures.

Contribution

It introduces the first demonstration of charge-tunable, optically active III-Nitride quantum dots with confirmed single-electron charging capabilities.

Findings

Confirmed single-electron charging through voltage-dependent energy shifts

Identified fundamental energy structures including neutral and charged excitons

Established potential for coherent control of charges in III-Nitride QDs

Abstract

III-Nitride quantum dots have emerged as a new chip-scale system for quantum information science, which combines electrical and optical interfaces on a semiconductor chip that is compatible with non-cryogenic operating temperatures. Yet most work has been limited to optical excitations. To enable single-spin based quantum optical and quantum information research, we demonstrate here quantized charging in optically active, site-controlled III-Nitride quantum dots. Single-electron charging was confirmed by the voltage dependence of the energy, dipole moment, fine structures and polarization properties of the exciton states in the quantum dots. The fundamental energy structures of the quantum dots were identified, including neutral and charged excitons, fine structures of excitons, and A and B excitons. The results lay the ground for coherent control of single charges in III-Nitride QDs, opening a door to III-Nitride based spintronics and spin-qubit quantum information processing.