High-resolution neutron-scattering study of the roton in confined superfluid ⁴He

Journal Article · Tue Jun 01 04:00:00 EDT 1999 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.59.13588· OSTI ID:348261

Anderson, C. R. ^[1]; Andersen, K. H. ^[1]; Bossy, J. ^[2]; Stirling, W. G. ^[3]; Dimeo, R. M. ^[4]; Sokol, P. E. ^[4]; Cook, J. C. ^[5]; Brown, D. W. ^[6]

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1. Institut Laue-Langevin, Boite Postale 156, 38042 Grenoble, Cedex 9 (France)
2. Centre de Recherches sur les Tres Basses Temperatures-CNRS, Boite Postale 166, 338042 Grenoble, Cedex 9 (France)
3. Department of Physics, University of Liverpool, Liverpool L69 7ZE (United Kingdom)
4. Pennsylvania State Univ., University Park, PA (United States). Dept. of Physics
5. National Institute of Science and Technology, Gaithersburg, Maryland 20899 (United States)
6. Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Los Alamos Neutron Science Center (LANSCE), Lujan Neutron Scattering Center

We report high-resolution neutron inelastic-scattering measurements of the roton energy and linewidth of superfluid ⁴He confined in 95% porosity aerogel glass for temperatures 0.08<T<1.2 K. The confined roton line shape can be described well by a damped harmonic oscillator (DHO) function, as in the bulk. The energy of the confined roton is essentially temperature independent over this temperature range. The roton linewidth does not exhibit a finite width of greater than 0.1 μeV at low temperature. This result is in contrast to previous measurements carried out at lower resolution.

• OSTI ID: 348261
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 21 Vol. 59; ISSN 0163-1829
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
HELIUM 4
LINE WIDTHS
NEUTRON DIFFRACTION
ROTONS
SUPERFLUIDITY