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Updated: May 23, 2026
12:57
Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
Ultrafast photon-photon interaction in a strongly coupled quantum dot-cavity system
Dirk Englund1, Arka Majumdar, Michal Bajcsy
1E. L. Ginzton Laboratory, Stanford University, Stanford, California 94305, USA. englund@columbia.edu
Physical Review Letters
|April 3, 2012
Summary
We demonstrate fast, controllable optical switching using a quantum dot-nanocavity system. This quantum system enables single-photon level light beam manipulation for advanced optical applications.
Area of Science:
- Quantum optics
- Solid-state physics
- Nanophotonics
Background:
- Strongly coupled quantum dot-photonic crystal cavity systems are promising for optical control.
- All-optical switching is crucial for high-speed information processing.
Purpose of the Study:
- To investigate the dynamics of light-light interactions mediated by a quantum dot-nanocavity system.
- To demonstrate all-optical switching capabilities at the single-photon level.
Main Methods:
- Utilized a strongly coupled quantum dot-photonic crystal cavity system.
- Performed all-optical switching of a continuous-wave signal with a pulsed beam.
- Demonstrated switching between two weak pulsed beams (40 ps pulses).
Main Results:
- Achieved all-optical switching of weak light beams.
- Showcased controllable switching using the quantum dot-nanocavity system.
- Confirmed operation at the single-photon level.
Conclusions:
- Quantum dot-nanocavity systems facilitate fast and controllable optical switching.
- The demonstrated switching is effective at the single-photon level.
- This technology holds potential for future optical communication and computing.
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