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Updated: Aug 8, 2026

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Knight-field-enabled nuclear spin polarization in single quantum dots
C W Lai1, P Maletinsky, A Badolato
1Institute of Quantum Electronics, ETH-Zürich, CH-8093 Zürich, Switzerland.
Abstract:
We demonstrate dynamical nuclear-spin polarization in the absence of an external magnetic field by resonant circularly polarized optical excitation of a single electron or hole charged quantum dot. Optical pumping of the electron spin induces an effective inhomogeneous magnetic (Knight) field that determines the direction along which nuclear spins could polarize and enables nuclear-spin cooling by suppressing depolarization induced by nuclear dipole-dipole interactions. Our experiments constitute a first step towards a quantum measurement of the Overhauser field.
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