High-Frequency Acoustics of <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow></mrow><mrow><mn>3</mn></mrow></msup></mrow><mi>He</mi></math></span> in Aerogel

R. Nomura; G. Gervais; T. M. Haard; Y. Lee; N. Mulders; W. P. Halperin

doi:10.1103/PhysRevLett.85.4325

High-Frequency Acoustics of $^{3} He$ in Aerogel

R. Nomura, G. Gervais, T. M. Haard, Y. Lee, N. Mulders, and W. P. Halperin

Phys. Rev. Lett. 85, 4325 – Published 13 November 2000

Abstract

High-frequency $(\sim 15 MHz)$ acoustics were performed on $^{3} He$ in $98 %$ porous silica aerogel using an acoustic cavity technique. Measurements of the sound attenuation in the normal Fermi liquid and superfluid display behavior quite different from the bulk owing to strong elastic scattering of quasiparticles. The transition from first-to-zero sound is completely obscured with a quasiparticle mean-free path estimated to be in the range of 200–300 nm. No collective mode attenuation peak was observed at or below the superfluid transition.

Received 30 May 2000

DOI:https://doi.org/10.1103/PhysRevLett.85.4325

Authors & Affiliations

R. Nomura^1,*, G. Gervais¹, T. M. Haard¹, Y. Lee^1,†, N. Mulders², and W. P. Halperin¹

¹Department of Physics and Astronomy, Northwestern University, Evanston, Illinois, 60208
²Department of Physics and Astronomy, University of Delaware, Newark, Delaware, 19716

^*Present address: Department of Condensed Matter Physics, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8551, Japan.
^†Present address: Department of Physics, Stanford University, Stanford, California 94305.