Negative group velocity and Kelvin-like wake pattern

Article

关键词: VORTEX NUCLEATION;   

DOI  :  10.1103/PhysRevB.105.054509

来源: SCIE

【 摘 要 】

Wake patterns due to a uniformly traveling source are a result of the resonant emission of the medium's collective excitations. When there exists a frequency range where such excitations possess a negative group velocity, their interference leads to a wake pattern resembling the Kelvin ship wake: while there are transverse and divergent wave fronts trailing the source, they are oriented oppositely to Kelvin's. This is illustrated by an explicit calculation of roton wake patterns in superfluid 4He where a Kelvin-like wake emerges when the speed of the source marginally exceeds the Landau critical roton velocity.

【 授权许可】

Free