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Updated: Jul 4, 2026
12:57
Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
Postselective two-photon interference from a continuous nonclassical stream of photons emitted by a quantum dot
R B Patel1, A J Bennett, K Cooper
1Toshiba Research Europe Limited, Cambridge Research Laboratory, 208 Cambridge Science Park, Milton Road, Cambridge, CB4 0GZ, United Kingdom. rp349@cam.ac.uk
Physical Review Letters
|June 4, 2008
Summary
We developed an electrically driven semiconductor single-photon source that emits photons with long coherence times. Higher injection currents reduce coherence, a phenomenon explained by environmental modulation, enabling quantum interference experiments.
Area of Science:
- Quantum Optics
- Solid-State Physics
- Photonics
Background:
- Single-photon sources are crucial for quantum information processing and quantum communication.
- Semiconductor-based single-photon sources offer potential for on-chip integration and scalability.
- Photon coherence time is a key parameter determining the performance of quantum protocols.
Purpose of the Study:
- To report an electrically driven semiconductor single-photon source with significant coherence time.
- To investigate the influence of injection current on photon coherence.
- To demonstrate two-photon interference for assessing photon indistinguishability.
Main Methods:
- Fabrication and characterization of an electrically driven semiconductor single-photon source.
- Measurement of photon coherence time under varying injection currents.
- Implementation of a Mach-Zehnder interferometer for Hong-Ou-Mandel interference experiments.
Main Results:
- Achieved a coherence time of up to 400 ps under fixed bias.
- Observed a reduction in coherence time with increasing injection current, attributed to environmental modulation.
- Demonstrated Hong-Ou-Mandel two-photon interference, confirming photon indistinguishability.
Conclusions:
- The developed semiconductor single-photon source is suitable for quantum interference experiments.
- Understanding the impact of injection current on coherence is vital for source optimization.
- Future improvements in detection systems can enhance interference visibility for advanced quantum applications.
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