Physics and Astronomy Quantum Nano Seminar - Shih-Chuan Gou

"Kibble-Zurek Scaling and its Breakdown for Spontaneous Generation of Josephson Vortices in Bose-Einstein Condensates"

October 3, 2013
4 pm - 5 pm
Location
Wilder 202
Sponsored by
Physics & Astronomy Department
Audience
Public
More information
Tressena Manning
603-646-2854
Abstract: Atomic Bose-Einstein condensates confined to a dual-ring trap support Josephson vortices as topo- logically stable defects in the relative phase. We propose a test of the scaling laws for defect formation by quenching a Bose gas to degeneracy in this geometry. Stochastic Gross-Pitaevskii simulations reveal a -1/4 power-law scaling of defect number with quench time for fast quenches, consistent with the Kibble- Zurek mechanism. Slow quenches show stronger quench-time dependence that is explained by the stability properties of Josephson vortices, revealing the boundary of the Kibble-Zurek regime. Interference of the two atomic fields enables clear long-time measurement of stable defects and a direct test of the Kibble-Zurek mechanism in Bose-Einstein condensation.
 
Location
Wilder 202
Sponsored by
Physics & Astronomy Department
Audience
Public
More information
Tressena Manning
603-646-2854