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arXiv · 1302.6759

Voltage tunability of single spin-states in a quantum dot

Anthony J. Bennett·Matthew A. Pooley·Yameng Cao·Niklas Sköld·Ian Farrer·David A. Ritchie·Andrew J. Shields
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Abstract

Single spins in the solid-state offer a unique opportunity to store and manipulate quantum information, and to perform quantum-enhanced sensing of local fields and charges. Optical control of these systems using techniques developed in atomic physics has yet to exploit all the advantages of the solid-state. We demonstrate voltage tunability of the spin energy levels in a single quantum dot by modifying how spins sense magnetic field. We find the in-plane g-factor varies discontinuously for electrons, as more holes are loaded onto the dot. In contrast, the in-plane hole g-factor varies continuously. The device can change the sign of the in-plane g-factor of a single hole, at which point an avoided crossing is observed in the two spin eigenstates. This is exactly what is required for universal control of a single spin with a single electrical gate.

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Anthony J. Bennett, Matthew A. Pooley, Yameng Cao, Niklas Sköld, Ian Farrer, David A. Ritchie, Andrew J. Shields. 2013-02-27. Voltage tunability of single spin-states in a quantum dot. https://doi.org/10.1038/ncomms2519

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