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Observation of a new excitation in bcc solid 4He by inelastic neutron scattering

T. Markovich·E. Polturak·J. Bossy·E. Farhi
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Abstract

We report neutron scattering measurements of the phonons in bcc solid 4He. In general, only 3 accoustic phonon branches should exist in a monoatomic cubic crystal. In addition to these phonon branches, we found a new ''optic-like'' mode along the [110] direction. One possible interpretation of this new mode is in terms of localized excitations unique to a quantum solid.

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T. Markovich, E. Polturak, J. Bossy, E. Farhi. 2002-03-05. Observation of a new excitation in bcc solid 4He by inelastic neutron scattering. https://doi.org/10.1103/physrevlett.88.195301

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