TY - JOUR KW - pfc AU - V. Schweikhard AU - S. Tung AU - Eric Cornell BT - Physical Review Letters DA - 2007-07 DO - 10.1103/PhysRevLett.99.030401 PY - 2007 SE - 030401 T2 - Physical Review Letters TI - Vortex Proliferation in the Berezinskii-Kosterlitz-Thouless Regime on a Two-Dimensional Lattice of Bose-Einstein Condensates VL - 99 SN - 0031-9007 ER -