Predicted Signature of the Quantum Statistical Nature of Vortices in Bose-Einstein Condensates
Z Dutton, L V. Hau
Vortices are robust, particle-like excitations which occur in a variety of fluids. A tell-tale characteristic of superfluids is the existence only of vortices with quantized circulation. Quantized vortices have been observed in superfluid helium1 superconductors2 and in experiments with atomic Bose-Einstein condensates (BECs)3-9. An outstanding question of great controversy is whether vortices are bosons, fermions, or anyons10-13. In one and two-dimensional systems, identical quantum particles can obey anyon statistics which are in between those of bosons and fermionsu14-16. We report on development of a quantum field theory for a many-body interacting system of identical, quantized vortices. For a pancake shaped atomic BEC in a rotating potential, we calculate the quantum ground state and low-lying excited states for a quantum fluid of vortices. We present results for experimentally realizable parameter regimes where bosonic and fermionic vortex statistics lead to dramatic differences of the ground state properties. This will allow direct, experimental determination of the true quantum statistical nature of vortices.