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Geometrical Pumping with a Bose-Einstein Condensate.

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.

SUBMITTER: Lu HI

PROVIDER: S-EPMC5100700 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Geometrical Pumping with a Bose-Einstein Condensate.

Lu H-I HI Schemmer M M Aycock L M LM Genkina D D Sugawa S S Spielman I B IB

Physical review letters 20160520 20

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 p ...[more]

PMID: 27258857

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