Geometrical pumping with a Bose-Einstein condensate #MMPMID27258857
Lu HI; Schemmer M; Aycock LM; Genkina D; Sugawa S; Spielman IB
Phys Rev Lett 2016[May]; 116 (20): 200402 PMID27258857show ga
We realized a quantum geometric ?charge? pump for a Bose-Einstein condensate (BEC) in the lowest Bloch band of a novel bipartite magnetic lattice. Topological charge pumps in filled bands yield quantized pumping set by the global ? topological ? properties of the bands. In contrast, our geometric charge pump for a BEC occupying just a single crystal momentum state exibits non-quantized charge pumping set by local ? geometrical ? properties of the band structure. Like topological charge pumps, for each pump cycle we observed an overall displacement (here, not quantized) and a temporal modulation of the atomic wavepacket?s position in each unit cell, i.e., the polarization.