Cusp at ω = 2 Δ0 (T) in Ultrasound Dispersion Relation of Low Temperature Superfluid 3He-A
Abstract
The dispersion relation of the ultrasound in the low temperature3He-A has a cusp just at ω = 2 Δ0 (T)(Δ0(T) the maximum gap of 3He-A). It is shown that thecusp has a nonanalyticity of the form 1/ln| ω / 2 Δ0 (T)-1 |. The output change of acoustic impedance detected recently by Meisel et al., is attributed to this cusp. The dispersion relation including the Landau parameter F2S is also given.
- Publication:
-
Progress of Theoretical Physics
- Pub Date:
- December 1983
- DOI:
- 10.1143/PTP.70.1672
- Bibcode:
- 1983PThPh..70.1672A