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Micro-magnets for coherent control of spin-charge qubit in lateral quantum dots

M. Pioro-Ladriere·Y. Tokura·T. Obata·T. Kubo·S. Tarucha
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Abstract

A lateral quantum dot design for coherent electrical manipulation of a two-level spin-charge system is presented. Two micron-size permanent magnets integrated to high-frequency electrodes produce a static slanting magnetic field suitable for voltage controlled single qubit gate operations. Stray field deviation from the slanting form is taken into account in the Hamiltonian describing the two-level system, which involves hybridization of a single electron spin to the quantum dot's orbitals. Operation speed and gate fidelity are related to device parameters. Sub 100 ns $π$ pulse duration can be achieved with lattice fluctuations coherence time of 4 ms for GaAs.

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M. Pioro-Ladriere, Y. Tokura, T. Obata, T. Kubo, S. Tarucha. 2006-12-13. Micro-magnets for coherent control of spin-charge qubit in lateral quantum dots. https://doi.org/10.1063/1.2430906

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