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Exciting the Higgs Mode in a Strongly Interacting Fermi Gas by Interaction Modulation
Andreas Kell1, Moritz Breyer1, Daniel Eberz1
1Physikalisches Institut, <a href="https://ror.org/041nas322">University of Bonn</a>, Wegelerstraße 8, 53115 Bonn, Germany.
Physical Review Letters
|October 25, 2024
Summary
Researchers studied the Higgs mode in a strongly interacting Fermi gas, observing its resonance frequency and line width. The findings show unexpected temperature independence, offering insights into quantum gas behavior.
Area of Science:
- Quantum Gas Physics
- Condensed Matter Physics
Background:
- Superfluidity in Fermi gases exhibits a crossover from fermionic to bosonic behavior.
- The Higgs mode, a collective excitation, is a key feature in gapped systems like superfluids.
Purpose of the Study:
- To investigate the Higgs mode in a strongly interacting Fermi gas within the fermionic-bosonic crossover regime.
- To analyze the resonance frequency and line width of the parametrically excited Higgs mode.
- To determine the dependence of these properties on interaction strength and temperature.
Main Methods:
- Utilizing a strongly interacting Fermi gas.
- Periodically modulating the interaction strength to parametrically excite the Higgs mode.
- Measuring the resonance frequency and line width of the Higgs mode.
Main Results:
- The resonance frequency at low temperatures aligns with theoretical predictions based on the pairing gap.
- Both the resonance frequency and line width show minimal variation with temperature.
- This temperature independence is unexpected theoretically but consistent with some recent findings.
Conclusions:
- The study provides experimental data on the Higgs mode in a unique quantum gas regime.
- The observed temperature independence challenges theoretical expectations, suggesting further investigation is needed.
- This research contributes to understanding collective excitations in strongly correlated quantum systems.
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