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Optical pumping of quantum dot nuclear spins

A. Imamoglu·E. Knill·L. Tian·P. Zoller
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Abstract

An all-optical scheme to polarize nuclear spins in a single quantum dot is analyzed. The hyperfine interaction with randomly oriented nuclear spins presents a fundamental limit for electron spin coherence in a quantum dot; by cooling the nuclear spins, this decoherence mechanism could be suppressed. The proposed scheme is inspired by laser cooling methods of atomic physics and implements a "controlled Overhauser effect" in a zero-dimensional structure.

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A. Imamoglu, E. Knill, L. Tian, P. Zoller. 2003-03-27. Optical pumping of quantum dot nuclear spins. https://doi.org/10.1103/physrevlett.91.017402

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