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Updated: Jul 15, 2026
11:21
Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Mode locking of a driven Bose-Einstein condensate
Alexandru I Nicolin1, Mogens H Jensen, R Carretero-González
1Niels Bohr Institute, Blegdamsvej 17, Copenhagen Ø, DK-2100, Denmark. nicolin@nbi.dk
Summary
We found that Bose-Einstein condensates respond to modulated scattering lengths by locking their frequency to the eigenfrequency. This phenomenon is explained by an auto-resonance model, akin to a particle in a potential well.
Area of Science:
- Quantum physics
- Atomic physics
- Condensed matter physics
Background:
- Bose-Einstein condensates (BECs) are quantum states of matter.
- Their dynamics are governed by interactions, often characterized by scattering length.
- Modulating physical parameters can lead to novel dynamic behaviors.
Purpose of the Study:
- To investigate the dynamic response of a driven Bose-Einstein condensate.
- To explore the effect of time-modulated scattering length on condensate behavior.
- To identify and explain frequency locking phenomena.
Main Methods:
- Variational treatment of the condensate dynamics.
- Time modulation of the scattering length with linearly increasing frequency.
- Development of an analytical model for phenomenon explanation.
Main Results:
- Observed frequency locking of the condensate response to its eigenfrequency.
- The locking occurs for small modulation amplitudes (epsilon) and frequency sweep rates (gamma).
- An analytical model successfully explains the locking via an auto-resonance mechanism.
Conclusions:
- Time-modulated scattering length in BECs can induce frequency locking.
- The phenomenon is analogous to auto-resonance, described by an effective potential.
- This provides insights into the control and manipulation of quantum systems.
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