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Updated: Jun 24, 2025
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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Stochastic circular persistent currents of exciton polaritons.
J Barrat1,2, Roman Cherbunin3, Evgeny Sedov4,5,6,7
1Key Laboratory for Quantum Materials of Zhejiang Province, Department of Physics, School of Science, Westlake University, 600 Dunyu Road, Hangzhou, 310030, Zhejiang, China.
Scientific Reports
|June 5, 2024
Summary
Researchers observed stochastic switching in exciton-polariton condensates within optical traps. A control pulse transitioned the system to a deterministic regime, enabling controlled polariton circulation.
Area of Science:
- Condensed matter physics
- Quantum optics
Background:
- Exciton-polariton condensates exhibit complex dynamics under external stimuli.
- Persistent annular currents in confined systems are crucial for quantum device applications.
Purpose of the Study:
- To investigate the orbital dynamics of exciton-polariton condensates.
- To understand the stochastic switching of polariton currents.
- To explore methods for controlling polariton circulation direction.
Main Methods:
- Monitoring orbital degrees of freedom in optical traps.
- Utilizing pulse-periodic excitation.
- Performing interference experiments to extract phase information.
- Introducing supplemental control optical pulses.
Main Results:
- Observed stochastic switching of persistent annular polariton currents.
- Identified a two-petaled density distribution with swirling phase in elliptical traps.
- Demonstrated azimuthal homogenization of density distribution in the stochastic regime.
- Revealed compensatory phase jumps around the trap center.
- Showcased transition from stochastic to deterministic regime with control pulses.
Conclusions:
- The study reveals controllable stochastic dynamics in exciton-polariton condensates.
- A supplemental pulse can break system reciprocity and control polariton circulation.
- Findings offer insights into manipulating quantum fluid behavior for future applications.
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