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Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
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GaAs Cone-Shell Quantum Dots in a Lateral Electric Field: Exciton Stark-Shift, Lifetime, and Fine-Structure Splitting
Ahmed Alshaikh1, Robert H Blick1, Christian Heyn1
1Center for Hybrid Nanostructures (CHyN), University of Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany.
Nanomaterials (Basel, Switzerland)
|July 26, 2024
Summary
Strain-free gallium arsenide (GaAs) cone-shell quantum dots exhibit tunable optical properties under lateral electric fields. These fields induce charge-carrier polarization, forming dipoles that influence exciton energy and fine-structure splitting.
Area of Science:
- Solid State Physics
- Quantum Optics
- Materials Science
Background:
- Strain-free GaAs cone-shell quantum dots possess unique geometries enabling tunable charge-carrier dynamics via external fields.
- Understanding the impact of electric fields is crucial for controlling quantum dot optical emission.
Purpose of the Study:
- To experimentally investigate the influence of lateral electric fields on the optical emission of GaAs cone-shell quantum dots.
- To validate simulation predictions regarding charge-carrier behavior under electric fields.
Main Methods:
- Integration of quantum dots into a lateral gate geometry.
- Single-dot photoluminescence spectroscopy to measure exciton energy Stark-shift, intensity, radiative lifetime, and fine-structure splitting (FSS).
- Analysis of gate voltage dependencies to identify distinct operational regimes.
Main Results:
- Observed three distinct regimes in gate voltage dependence: charge-carrier deformation, vertical shift, and lateral polarization.
- Demonstrated that lateral polarization forms a dipole, modulating the intrinsic FSS based on electric field orientation.
- Showed suppression of the biexciton peak, attributed to an induced vertical electric field.
Conclusions:
- Lateral electric fields induce predictable charge-carrier polarization and dipole formation in GaAs cone-shell quantum dots.
- The observed regimes offer insights into controlling quantum dot optical properties.
- Potential for tuning FSS and suppressing biexcitons through electric field manipulation.
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