Abstract

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 exhibits nonquantized 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 wave packet s position in each unit cell, i.e., the polarization.

Publication Details
Publication Type
Journal Article
Year of Publication
2016
Volume
116
DOI
10.1103/PhysRevLett.116.200402
Journal
Physical Review Letters
Contributors