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Spontaneous Formation of Star-Shaped Surface Patterns in a Driven Bose-Einstein Condensate
K Kwon1, K Mukherjee2, S J Huh1
1Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea.
Physical Review Letters
|September 24, 2021
Summary
Researchers observed star-shaped surface patterns in Bose-Einstein condensates. The study identified specific modes, like the l=6 mode, becoming unstable due to coupling, advancing quantum fluid research.
Area of Science:
- Quantum physics
- Condensed matter physics
Background:
- Bose-Einstein condensates (BECs) are quantum states of matter.
- Surface excitations in superfluids are crucial for understanding quantum fluid dynamics.
Purpose of the Study:
- To experimentally observe and characterize spontaneous star-shaped surface patterns in driven Bose-Einstein condensates.
- To investigate the parametric excitation of these patterns and their symmetries.
Main Methods:
- Parametric excitation of Bose-Einstein condensates by modulating scattering length near a Feshbach resonance.
- Utilizing an effective Mathieu equation and Floquet analysis to study instability conditions.
- Precisely measuring the dispersion relation of collective excitations by identifying resonant frequencies.
Main Results:
- Observation of spontaneous formation of 2D star-shaped patterns with l-fold symmetry (l=2 to l=7).
- Identification of the l=6 mode as uniquely unstable due to emergent coupling with dipole motion.
- Exponential increase in oscillation amplitude of surface excitations during modulation.
Conclusions:
- Experimental findings align well with the mean-field framework.
- The study provides a new method for generating higher-lying collective excitations.
- Opens pathways for probing exotic quantum fluid properties and generating quantum turbulence.
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