Year: 2025
Type: article
Abstract: We show that two-component Bose-Einstein condensed mixtures, in presence of a persistent current, exhibit a nontrivial Doppler shift of the sound velocities. The peculiarity is due to the interspecies interaction and the possibility of generating a counterflow persistent current. Analytical predictions are derived using superfluid hydrodynamics. While the existence of anomalous Doppler shifts at finite temperature has been discussed a long time ago in the case of superfluid $^{4}\mathrm{He}$, an experimental verification of the effect is still missing. For this reason, we also propose a protocol for the measurement of the Doppler shifts, based on the density-density response function. The dynamical protocol is simulated by means of coupled Gross-Pitaevskii equations.
Source: Physical Review A
DOI: 10.1103/yc6t-13d4
Authors: Tomasz Zawiślak, Sandro Stringari, Alessio Recati
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4417267583