Spectral Weight, Excitation Stability and Critical Velocity in a Bose-Condensed Gas
نویسندگان
چکیده
منابع مشابه
Evidence for a Critical Velocity in a Bose-Einstein Condensed Gas
where ́ is the energy of an excitation with momentum p. Critical velocities for the breaking of Cooper pairs in 3He and the generation of rotons [2] and vortices [3] in 4He have been extensively studied. Bose-Einstein condensed gases (BEC) are novel quantum fluids [4]. Previous work has explored some aspects related to superfluidity such as the macroscopic phase [5] and the phonon nature of low-...
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ژورنال
عنوان ژورنال: Progress of Theoretical Physics
سال: 2002
ISSN: 0033-068X,1347-4081
DOI: 10.1143/ptp.107.903