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arXiv · 2302.05489

Approaching a fully-polarized state of nuclear spins in a semiconductor quantum dot

Peter Millington-Hotze·Harry E. Dyte·Santanu Manna·Saimon F. Covre da Silva·Armando Rastelli·Evgeny A. Chekhovich
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Abstract

Magnetic noise of atomic nuclear spins is a major problem for solid state spin qubits. Highly-polarized nuclei would not only overcome this obstacle, but also make nuclear spins a useful quantum information resource. However, achieving sufficiently high nuclear polarizations has remained an evasive goal. Here we implement a nuclear spin polarization protocol which combines strong optical pumping and fast electron tunneling. Polarizations well above 95% are generated in GaAs semiconductor quantum dots on a timescale of 1 minute. The technique is compatible with standard quantum dot device designs, where highly-polarized nuclear spins can simplify implementations of quantum bits and memories, as well as offer a testbed for studies of many-body quantum dynamics and magnetism.

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Peter Millington-Hotze, Harry E. Dyte, Santanu Manna, Saimon F. Covre da Silva, Armando Rastelli, Evgeny A. Chekhovich. 2023-02-10. Approaching a fully-polarized state of nuclear spins in a semiconductor quantum dot. https://doi.org/10.1038/s41467-024-45364-2

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