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Critical fluctuations in a confined driven-dissipative quantum condensate
Hassan Alnatah1, Paolo Comaron2, Shouvik Mukherjee3
1Department of Physics, University of Pittsburgh, 3941 O'Hara Street, Pittsburgh, PA 15218, USA.
Science Advances
|March 22, 2024
Summary
Researchers observed critical quantum fluctuations in polariton condensates near the condensation threshold. This quantum state competition, analogous to photon lasers, offers new insights into condensate formation.
Area of Science:
- Quantum optics
- Condensed matter physics
- Non-equilibrium systems
Background:
- Phase fluctuations dominate quantum condensates away from the critical point.
- Number fluctuations are less explored, especially near condensation thresholds.
- Understanding fluctuations is key to characterizing quantum systems.
Purpose of the Study:
- To experimentally observe and theoretically describe fluctuations in a nonequilibrium Bose-Einstein condensate of polaritons.
- To investigate the nature of fluctuations near the condensation threshold.
- To explore the role of quantum effects versus classical noise.
Main Methods:
- Experimental observation of polariton condensates in circular confinement.
- Theoretical analysis of critical fluctuations.
- Comparison of quantum phenomena with classical noise effects.
Main Results:
- Experimental observation of critical fluctuations combining number fluctuations and state competition.
- Theoretical analysis confirms the quantum nature of the observed phenomenon.
- Classical pump noise is insufficient to explain the experimental results.
Conclusions:
- The study reveals critical quantum state competition in polariton condensates near the threshold.
- This phenomenon is analogous to mode hopping in photon lasers.
- Findings open avenues for studying condensate formation and have implications for photonic lasers.
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