Condensed Matter Physics Commons^™

Kinetic Theory Of Dark Solitons With Tunable Friction, Hilary M. Hurst, Dimitry K. Efimkin, I. B. Spielman, Victor Galitski

Faculty Research, Scholarly, and Creative Activity

We study controllable friction in a system consisting of a dark soliton in a one-dimensional Bose-Einstein condensate coupled to a non-interacting Fermi gas. The fermions act as impurity atoms, not part of the original condensate, that scatter off of the soliton. We study semi-classical dynamics of the dark soliton, a particle-like object with negative mass, and calculate its friction coefficient. Surprisingly, it depends periodically on the ratio of interspecies (impurity-condensate) to intraspecies (condensate-condensate) interaction strengths. By tuning this ratio, one can access a regime where the friction coefficient vanishes. We develop a general theory of stochastic dynamics for negative mass …