Journal of Physics B Atomic Molecular and Optical Physics
Finite boson and fermion systems under extreme rotation: edge reconstruction and vortex formation
M. Toreblad, Y. C. Yu, S. M. Reimann, M. Koskinen, M. Manninen
Abstract
Vortices can form when finite quantal systems are set rotating. In the limit of small particle numbers, the vortex formation in a harmonically trapped fermion system, with repulsively interacting particles, shows similarities to the corresponding boson system, with vortices entering the rotating cloud for increasing rotation. For a larger number of fermions, N ≳ 15, the fermion vortices compete and co-exist with (Chamon–Wen) edge-reconstructed ground states, forcing some ground states, as for example the central single vortex, into the spectrum of excited states. Experimentally, the fermion system could, for instance, be electrons in a semiconductor heterostructure, a quantum dot, and the corresponding boson system, a Bose–Einstein condensate in a magneto optical trap.