Phonon Dispersion in Liquid Helium under Pressure

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23 October 1972

journal article
research article
Published by American Physical Society (APS) in Physical Review Letters

Vol. 29 (17) , 1148-1149
https://doi.org/10.1103/physrevlett.29.1148

Abstract

We have studied one-phonon neutron scattering in liquid helium at a pressure of 24 atm in the range of wave-vector transfers

0.2 Å^{- 1} <~ | \vec{Q} | <~ 0.7 Å^{- 1}

at

T = 1.2

K. The results give a value (6.2 ± 0.6) ×

10^{37}

g^{- 2}

{cm}^{- 2}

\sec^{2}

for the parameter

γ

which characterizes the phonon dispersion. The one-phonon peaks exhibit tails indicating shortened phonon life-times at elevated pressures.

Keywords

This publication has 12 references indexed in Scilit:

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