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Defect Saturation in a Rapidly Quenched Bose Gas
Junhong Goo1, Younghoon Lim1,2, Y Shin1,2,3
1Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea.
Physical Review Letters
|September 24, 2021
Summary
Defect density saturation in atomic Bose gases is observed during rapid cooling into a superfluid phase. This saturation is due to early-time coarsening, not vortex collisions, revealing dynamics beyond the Kibble-Zurek mechanism.
Area of Science:
- Quantum physics
- Condensed matter physics
- Atomic physics
Background:
- Superfluid phase transitions involve defect formation.
- The Kibble-Zurek (KZ) mechanism describes defect creation during phase transitions.
Purpose of the Study:
- Investigate defect density saturation in atomic Bose gases during rapid cooling.
- Determine the mechanism behind vortex number saturation in quenched Bose gases.
Main Methods:
- Rapid cooling of an atomic Bose gas into a superfluid phase.
- Analysis of quantum vortex number distribution.
- Observation of condensate growth dynamics relative to quenching.
Main Results:
- Quantum vortex number distribution follows a Poissonian pattern for both slow and fast quenches.
- Mean vortex number saturates in fast quenches, deviating from KZ scaling.
- Saturation is attributed to early-time coarsening in the emerging condensate, not vortex collisions.
Conclusions:
- Defect saturation in quenched Bose gases is an effect beyond the standard Kibble-Zurek mechanism.
- The defect number distribution offers insights into critical phase transition dynamics.
- This work provides a new avenue for studying non-equilibrium quantum phenomena.
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