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Limits on transverse zero sound in Fermi liquid 3He
Man Dinh Nguyen1, Daehan Park1, John William Scott1
1Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208, USA.
Science Advances
|February 27, 2026
Summary
Researchers investigated Landau
Area of Science:
- Condensed matter physics
- Quantum fluids
Background:
- Landau predicted transverse sound in Fermi liquids.
- Previous attempts to detect this mode were inconclusive.
Purpose of the Study:
- To directly detect transverse sound in liquid 3He.
- To measure the acoustic impedance of the fluid.
Main Methods:
- Fabrication of microscale acoustic cavities.
- Utilizing acoustic Fabry-Pérot interference fringes.
- Measuring acoustic impedance (real and imaginary parts).
Main Results:
- No acoustic interference was observed.
- Transverse sound was not detected.
- Attenuation must be extremely high (>2000 cm⁻¹).
Conclusions:
- Transverse sound may not exist in liquid 3He under these conditions.
- Alternatively, its attenuation is significantly higher than previously thought.
- A theoretical framework for high attenuation is discussed.
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