Chiral edge states of vortex matter

Abstract

We study the evolution of the excitation spectrum of a trapped rotating Bose-Einstein condensate as a function of increasing rotational frequency and discuss chiral edge states supported on the condensate surface. We describe these modes in the context of a mean-field Bogoliubov--de Gennes treatment. We find that they dominate the spectrum at fast rotation, and the dispersion relation for these excitations becomes linear in the limit of high angular momentum as in the quantum Hall effect. We also identify the edge states as primary agents in the nucleation and decay of the lattice.