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Nuclear magnetization in gallium arsenide quantum dots at zero magnetic field.

ABSTRACT: Optical and electrical control of the nuclear spin system allows enhancing the sensitivity of NMR applications and spin-based information storage and processing. Dynamic nuclear polarization in semiconductors is commonly achieved in the presence of a stabilizing external magnetic field. Here we report efficient optical pumping of nuclear spins at zero magnetic field in strain-free GaAs quantum dots. The strong interaction of a single, optically injected electron spin with the nuclear spins acts as a stabilizing, effective magnetic field (Knight field) on the nuclei. We optically tune the Knight field amplitude and direction. In combination with a small transverse magnetic field, we are able to control the longitudinal and transverse components of the nuclear spin polarization in the absence of lattice strain--that is, in dots with strongly reduced static nuclear quadrupole effects, as reproduced by our model calculations.

SUBMITTER: Sallen G

PROVIDER: S-EPMC3926008 | biostudies-other | 2014

REPOSITORIES: biostudies-other

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Nuclear magnetization in gallium arsenide quantum dots at zero magnetic field.

Sallen G G Kunz S S Amand T T Bouet L L Kuroda T T Mano T T Paget D D Krebs O O Marie X X Sakoda K K Urbaszek B B

Nature communications 20140101

Optical and electrical control of the nuclear spin system allows enhancing the sensitivity of NMR applications and spin-based information storage and processing. Dynamic nuclear polarization in semiconductors is commonly achieved in the presence of a stabilizing external magnetic field. Here we report efficient optical pumping of nuclear spins at zero magnetic field in strain-free GaAs quantum dots. The strong interaction of a single, optically injected electron spin with the nuclear spins acts ...[more]

PMID: 24500329

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