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Updated: Apr 6, 2026
12:57
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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Spin-cavity interactions between a quantum dot molecule and a photonic crystal cavity
Patrick M Vora1, Allan S Bracker2, Samuel G Carter2
1NRC research associate residing at the Naval Research Laboratory, Washington, District of Columbia 20375, USA.
Nature Communications
|July 18, 2015
Summary
Researchers developed a two-spin-cavity system using InAs quantum dot molecules in a photonic crystal cavity. This system enables spin-selective Raman emission and cavity-enhanced nonlinearities for quantum network applications.
Area of Science:
- Quantum physics
- Nanophotonics
- Solid-state physics
Background:
- Cavity quantum electrodynamics (cQED) with quantum dots (QDs) typically uses two-level excitonic systems.
- Coupling long-lived quantum dot electron spin states with optical cavities is a recent advancement.
- Developing robust spin-cavity systems is crucial for quantum information processing.
Purpose of the Study:
- To create and investigate a two-spin-cavity system using InAs/GaAs quantum dot molecules.
- To demonstrate spin-selective optical control and cavity-enhanced nonlinearities.
- To explore the potential of QD molecules in photonic crystal cavities for quantum networks.
Main Methods:
- Embedding an InAs quantum dot molecule within a photonic crystal cavity.
- Creating a spin singlet-triplet Λ-system with significant ground-state spin splitting.
- Utilizing cavity-stimulated Raman emission for spin manipulation.
Main Results:
- Observed cavity-stimulated Raman emission with high spin selectivity.
- Achieved a spin singlet-triplet Λ-system where spin splitting greatly exceeds cavity linewidth.
- Demonstrated the first solid-state Λ-system exhibiting cavity-enhanced optical nonlinearities.
- Showcased an all-optical, local method for controlling spin exchange splitting.
Conclusions:
- The developed two-spin-cavity system offers a promising platform for quantum information processing.
- The use of engineerable quantum dot molecules in photonic crystals advances quantum network prospects.
- This work provides a novel approach for all-optical spin control in solid-state systems.
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