Scientific Results

Second sound in a two-dimensional Bose gas: From the weakly to the strongly interacting regime

Year: 2018

Authors: Ota M., Stringari S.

Autors Affiliation: [Ota, Miki] Univ Trento, INO CNR BEC Ctr, I-38123 Povo, Italy;
Univ Trento, Dipartimento Fis, I-38123 Povo, Italy.

Abstract: Using Landau’s theory of two-fluid hydrodynamics, we investigate first and second sounds propagating in a two-dimensional (2D) Bose gas. We study the temperature and interaction dependence of both sound modes and show that their behavior exhibits a deep qualitative change as the gas evolves from the weakly interacting to the strongly interacting regime. Special emphasis is placed on the jump of both sounds at the Berezinskii-Kosterlitz-Thouless transition, caused by the discontinuity of the superfluid density. We find that the excitation of second sound through a density perturbation becomes weaker and weaker as the interaction strength increases as a consequence of the decrease in the thermal expansion coefficient. Our results could be relevant for future experiments on the propagation of sound on the Bose-Einstein condensate (BEC) side of the BCS-BEC crossover of a 2D superfluid Fermi gas.

Journal/Review: PHYSICAL REVIEW A

Volume: 97 (3)      Pages from: 033604-1  to: 033604-7

KeyWords: Einstein condensate; Fermi gas; superfluidity; vortices; systems
DOI: 10.1103/PhysRevA.97.033604

Citations: 14
data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2021-10-10
References taken from IsiWeb of Knowledge: (subscribers only)
Connecting to view paper tab on IsiWeb: Click here
Connecting to view citations from IsiWeb: Click here

gdpr-image
This site uses cookies. If you decide to continue browsing we consider that you accept their use. For more information about cookies and how to delete them please read our Info Policy on cookies use.
Read more