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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Second-order time correlations within a polariton Bose-Einstein condensate in a CdTe microcavity
J Kasprzak1, M Richard, A Baas
1Institut Néel, CNRS/UJF, 25 avenue des Martyrs, BP 166 38042 Grenoble cedex 9, France.
Physical Review Letters
|March 21, 2008
Summary
Researchers observed Bose-Einstein condensation in polaritons, noting a shift from thermal to coherent states. Coherence decreased with higher polariton density, distinguishing this from photon lasing.
Area of Science:
- Quantum optics
- Condensation phenomena
- Solid-state physics
Background:
- Polaritons are quasiparticles formed from the interaction of photons and excitons.
- Bose-Einstein condensation (BEC) is a state of matter where particles occupy the lowest quantum state.
- Understanding BEC in different systems is crucial for quantum technologies.
Purpose of the Study:
- To investigate the characteristics of polariton Bose-Einstein condensation.
- To analyze the transition from thermal to coherent states in a CdTe microcavity.
- To differentiate polariton BEC from photon lasing.
Main Methods:
- Measurement of second-order time correlations of polaritons.
- Experiments conducted across the condensation threshold in a CdTe microcavity.
- Analysis of photon bunching behavior.
Main Results:
- The onset of Bose-Einstein condensation was identified by the disappearance of photon bunching.
- A transition from a thermal-like state to a coherent state was observed.
- Coherence degraded with increasing polariton density due to self-interaction and scattering.
Conclusions:
- Polariton Bose condensation exhibits distinct behavior compared to photon lasing.
- Self-interaction and scattering effects influence coherence in polariton condensates.
- The study provides insights into the fundamental properties of quantum condensates.
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