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Experimental Realization of a Quantum Spin Pump

Susan K. Watson·R. M. Potok·C. M. Marcus·V. Umansky
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Abstract

We demonstrate the operation of a quantum spin pump based on cyclic radio-frequency excitation of a GaAs quantum dot, including the ability to pump pure spin without pumping charge. The device takes advantage of bidirectional mesoscopic fluctuations of pumped current, made spin-dependent by the application of an in-plane Zeeman field. Spin currents are measured by placing the pump in a focusing geometry with a spin-selective collector.

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Susan K. Watson, R. M. Potok, C. M. Marcus, V. Umansky. 2003-06-01. Experimental Realization of a Quantum Spin Pump. https://doi.org/10.1103/physrevlett.91.258301

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