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Updated: Jun 26, 2025
00:07
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Breakdown of Temporal Coherence in Photon Condensates.
Yijun Tang1, Himadri S Dhar2, Rupert F Oulton1
1Physics Department, Blackett Laboratory, Imperial College London, Prince Consort Road, SW7 2AZ, United Kingdom.
Physical Review Letters
|May 10, 2024
Summary
Temporal coherence in Bose-Einstein condensates typically increases towards the critical point. However, photon condensates show decreased coherence above threshold due to intermode correlations, explaining experimental observations.
Area of Science:
- Quantum optics
- Condensed matter physics
- Bose-Einstein condensation
Background:
- Ideal Bose gases exhibit increasing temporal coherence approaching the Bose-Einstein condensation (BEC) threshold.
- Coherence time in ideal systems diverges at the critical point.
- Photon condensates in microcavities present a counterexample to this behavior.
Purpose of the Study:
- To explain the observed decrease in coherence time for photon condensates above the critical pump power.
- To identify the underlying mechanism responsible for reduced temporal coherence in experimental BEC systems.
Main Methods:
- Theoretical analysis of photon condensates in pumped microcavities.
- Investigation of intermode correlations within the condensate.
- Comparison of theoretical predictions with experimental observations of coherence time.
Main Results:
- Temporal coherence in photon condensates decreases rapidly above the critical pump power.
- Intermode correlations were identified as the primary cause for this decrease.
- The findings reconcile experimental data with theoretical expectations for BEC systems.
Conclusions:
- Intermode correlations are the central explanation for the reduced temporal coherence in pumped photon condensates.
- This mechanism clarifies deviations from ideal Bose gas behavior in experimental systems.
- Understanding these correlations is crucial for controlling coherence in photonic BECs.
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