Transition From Collisionless to Hydrodynamic Behavior in an Ultracold Atomic Gas
S D. Gensemer, D S. Jin
Relative motion in a two-component, trapped gas provides a sensitive probe of interactions. By studying the lowest frequency excitations of a two spin-state gas confined in a magnetic trap, we have explored the transition from the collisionless regime to the hydrodynamic regime. As a function of collsion rate, we observe frequency shifts as large as 7 % as well as a dramatic, non-monotonic dependence of the damping rate. The measurements agree qualitatively with expectations for behavior in the collisionless and hydrodynamic limits and are quantitatively compared to a classical kinetic model.
Physical Review Letters
damping, excitations, hydrodynamic
and Jin, D.
Transition From Collisionless to Hydrodynamic Behavior in an Ultracold Atomic Gas, Physical Review Letters
(Accessed December 5, 2023)