Charge control in InP/GaInP single quantum dots embedded in Schottky diodes

TL;DR

This paper demonstrates electric field control of charge states in single InP quantum dots within GaInP Schottky diodes, enabling detailed exciton characterization and electrical exciton studies.

Contribution

It introduces growth optimization to suppress large dot formation and combines optical and electrical methods for exciton analysis at the single-dot level.

Findings

Controlled charge states via electric field in InP quantum dots

Identification of exciton multi-particle states

Electrical characterization of exciton properties

Abstract

We demonstrate control by applied electric field of the charge states in single self-assembled InP quantum dots placed in GaInP Schottky structures grown by metalorganic vapor phase epitaxy. This has been enabled by growth optimization leading to suppression of formation of large dots uncontrollably accumulating charge. Using bias- and polarization-dependent micro-photoluminescence, we identify the exciton multi-particle states and carry out a systematic study of the neutral exciton state dipole moment and polarizability. This analysis allows for the characterization of the exciton wavefunction properties at the single dot level for this type of quantum dots. Photocurrent measurements allow further characterization of exciton properties by electrical means, opening new possibilities for resonant excitation studies for such system.