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arXiv · 1608.08153

Spin pumping and measurement of spin currents in optical superlattices

Christian Schweizer·Michael Lohse·Roberta Citro·Immanuel Bloch
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Abstract

We report on the experimental implementation of a spin pump with ultracold bosonic atoms in an optical superlattice. In the limit of isolated double wells it represents a 1D dynamical version of the quantum spin Hall effect. Starting from an antiferromagnetically ordered spin chain, we periodically vary the underlying spin-dependent Hamiltonian and observe a spin current without charge transport. We demonstrate a novel detection method to measure spin currents in optical lattices via superexchange oscillations emerging after a projection onto static double wells. Furthermore, we directly verify spin transport through in-situ measurements of the spins' center of mass displacement.

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Christian Schweizer, Michael Lohse, Roberta Citro, Immanuel Bloch. 2016-08-29. Spin pumping and measurement of spin currents in optical superlattices. https://doi.org/10.1103/physrevlett.117.170405

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