The group velocity of high-frequency sound for TTc, and the group velocity and attenuation of sound at higher temperatures, have been measured and analyzed to give the frequencies and coupling strengths of two order-parameter collective modes in He3-B. For the squashing mode at 13.1 bars and T→0, ωsqΔBCS=1.501 and the coupling constant λsq=0.010±0.001. The recently discovered collective mode at ωνΔBCS=1.075 (T→0) has a coupling constant determined from the group velocity to be λν=5.8×10-6.
ASJC Scopus subject areas
- Physics and Astronomy(all)