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Measuring the Joint Spectral Mode of Photon Pairs Using Intensity Interferometry
G S Thekkadath1,2, B A Bell1, R B Patel1,3
1Department of Physics, Imperial College London, Prince Consort Road, London SW7 2AZ, United Kingdom.
Physical Review Letters
|January 28, 2022
Summary
We developed a simple intensity interferometry method to measure the joint spectral mode of quantum light. This technique aids in creating high-purity quantum light sources for advanced applications.
Area of Science:
- Quantum Optics
- Quantum Information Science
Background:
- Manipulating quantum light's time-frequency structure is crucial for quantum information processing and metrology.
- Measuring the spectral structure of quantum light sources is vital for ensuring high modal purity and enabling interference with independent sources.
Purpose of the Study:
- To present and experimentally demonstrate a novel scheme for measuring the joint spectral mode of photon pairs.
- To investigate spectral phase correlations arising from pump chirp.
- To show the scheme's compatibility with stimulated emission tomography for rapid modal analysis.
Main Methods:
- Utilized intensity interferometry to measure the joint spectral mode of photon pairs from spontaneous parametric down-conversion.
- Observed spectral phase correlations attributed to pump chirp.
- Demonstrated combination with stimulated emission tomography for efficient modal measurement.
Main Results:
- Successfully measured the joint spectral mode of photon pairs.
- Identified and characterized spectral phase correlations linked to pump chirp.
- Showcased a method for rapid modal measurement using classical light.
Conclusions:
- The presented intensity interferometry scheme offers a simple and effective method for measuring the modal structure of quantum light.
- The technique does not necessitate phase stability, nonlinearities, or spectral shaping, simplifying experimental implementation.
- This approach facilitates the development of quantum light sources with improved modal purity for quantum technologies.
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