Variational theory of rotons in superfluid {sup 4}He

Journal Article · Wed Nov 01 04:00:00 EST 1995 · Journal of Low Temperature Physics

DOI:https://doi.org/10.1007/BF00753386· OSTI ID:183442

Galli, D E; Reatto, L ^[1]; Vitiello, S A ^[2]

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1. Universita di Milano (Italy)
2. International Center for Theoretical Physics, Trieste (Italy)

We have extended the shadow wave function for excited states by including an explicit backflow term in the shadow variables. The variational computation gives a roton energy 9.18 K, only 6% above experiment. Similar agreement is found at freezing density. Also the strength Z{sub q} of the single excitation peak greatly improves. The uniform agreement between theory and experiment at all wave vectors suggests that there is no qualitative difference in the wave function of phonon, maxon and roton excitations. Only the amount of backflow and short range correlations greatly varies with k.

• Sponsoring Organization: USDOE
• OSTI ID: 183442
• Report Number(s): CONF-950676--
• Journal Information: Journal of Low Temperature Physics, Journal Name: Journal of Low Temperature Physics Journal Issue: 3-4 Vol. 101; ISSN JLTPAC; ISSN 0022-2291
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
66 PHYSICS
EXCITED STATES
HELIUM 4
PHONONS
RESPONSE FUNCTIONS
ROTONS
SUPERFLUIDITY
VARIATIONAL METHODS
WAVE FUNCTIONS