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Published on: March 30, 2017
Condensation and vortex formation in a Bose gas upon cooling
E A Brener1, S V Iordanskiy, R B Saptsov
1Institut für Festkörperforschung, Forschungszentrum Jülich, 52425 Jülich, Germany.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 21, 2006
Summary
Critical fluctuations called instantons drive the transition of Bose gases to superfluidity. Their formation probability increases near the critical temperature, requiring vortex creation for instanton evolution.
Area of Science:
- Quantum mechanics
- Condensed matter physics
Background:
- Bose gases can transition to a superfluid state.
- Thermal fluctuations play a role in phase transitions.
Purpose of the Study:
- To investigate the mechanism of Bose gas transition to superfluidity via thermal fluctuations.
- To analyze the formation and evolution of critical fluctuations (instantons).
Main Methods:
- Theoretical calculation of instanton formation probability in 2D and 3D systems.
- Analysis of instanton evolution and its relation to vortex formation.
Main Results:
- Critical fluctuations (instantons) form above the critical temperature during external cooling.
- Instanton formation probability increases as the system approaches the transition temperature.
- Instanton evolution necessitates the formation of vortices in the superfluid component.
Conclusions:
- Thermal fluctuations, specifically instantons, are crucial for the Bose gas to superfluid transition.
- The probability of these critical fluctuations is temperature-dependent.
- Vortex formation is intrinsically linked to the dynamics of instantons in the superfluid state.
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