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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
Auger processes mediating the nonresonant optical emission from a semiconductor quantum dot embedded inside an
Mikkel Settnes1, Per Kaer, Anders Moelbjerg
1Department of Photonics Engineering, DTU Fotonik, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark. mikkel.settnes@gmail.com
Physical Review Letters
|August 27, 2013
Summary
Wetting layer transitions mediate quantum dot-cavity emission via Auger processes. This layer acts as a reservoir, explaining experimental cavity feeding asymmetries observed in quantum dot systems.
Area of Science:
- Quantum optics
- Condensed matter physics
- Semiconductor nanostructures
Background:
- Quantum dots coupled to optical cavities are crucial for quantum information processing.
- Cavity feeding, where emission is enhanced due to detuning, is a key phenomenon.
- Understanding the underlying mechanisms of cavity feeding is essential for device optimization.
Purpose of the Study:
- To investigate the role of Auger processes involving wetting layer transitions in quantum dot-cavity emission.
- To explain the experimentally observed asymmetric detuning in cavity feeding.
- To provide a theoretical framework for the wetting layer's influence on quantum dot-cavity interactions.
Main Methods:
- Microscopic calculations treating the wetting layer as a non-Markovian reservoir.
- Modeling Coulomb interactions between the quantum dot, cavity, and wetting layer.
- Numerical calculations of photoluminescence spectra and photon correlations.
Main Results:
- Auger processes involving wetting layer transitions mediate emission even with significant detuning (tens of meV).
- The wetting layer acts as an energy reservoir, supplying or absorbing detuning energy via Coulomb scattering.
- The model naturally explains the observed asymmetry in cavity feeding detuning (-10 to +45 meV).
Conclusions:
- Wetting layer transitions are a critical mechanism for mediating quantum dot-cavity emission.
- The wetting layer's reservoir properties are responsible for the asymmetric cavity feeding phenomenon.
- The theoretical model shows good qualitative agreement with experimental observations of photoluminescence and photon correlations.
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