Abstract
We present a theory of sound propagation in superfluid $^{3}\mathrm{He}$ confined in aerogel, taking dragged aerogel motion into account. The superfluid dynamics coupled with the aerogel motion is formulated by use of the Keldysh Green's function for weak-coupling superfluid Fermi liquid. We apply the theory to the hydrodynamic regime and calculate the attenuation of a hydrodynamic longitudinal sound mode, the so-called fast mode. The result is compared to the acoustic experiment reported by the Northwestern University group [R. Nomura, G. Gervais, T. M. Haard, Y. Lee, N. Mulders, and W. P. Halperin, Phys. Rev. Lett. 85, 4325 (2000); G. Gervais, R. Nomura, T. M. Haard, Y. Lee, N. Mulders, and W. P. Halperin, J. Low Temp. Phys. 122, 1 (2001)]. We find reasonable agreement between the theory and the experiment.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
