Charge tuning in [111] grown GaAs droplet quantum dots

Abstract

We demonstrate charge tuning in strain free GaAs/AlGaAs quantum dots (QDs) grown by droplet epitaxy on a GaAs(111)A substrate. Application of a bias voltage allows the controlled charging of the QDs from $-3|e|$ to $+2|e|$. The resulting changes in QD emission energy and exciton fine-structure are recorded in micro-photoluminescence experiments at T=4K. We uncover the existence of excited valence and conduction states, in addition to the s-shell-like ground state. We record a second series of emission lines about 25meV above the charged exciton emission coming from excited charged excitons. For these excited interband transitions a negative diamagnetic shift of large amplitude is uncovered in longitudinal magnetic fields.

5 pages, 3 figures

References in corpus (4)

• Nuclear spin physics in quantum dots: an optical investigation
• Optically Probing Spin and Charge Interactions in an Tunable Artificial Molecule
• Demagnetization of Quantum Dot Nuclear Spins: Breakdown of the Nuclear Spin Temperature Approach
• Complete control of a matter qubit using a single picosecond laser pulse

Cited by in corpus (2)

• Magneto-optics in transition metal diselenide monolayers
• Large-Range Frequency Tuning of a Narrow-Linewidth Quantum Emitter