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arXiv · 2201.06181

Charge-noise induced dephasing in silicon hole-spin qubits

Ognjen Malkoc·Peter Stano·Daniel Loss
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Abstract

We investigate theoretically charge-noise induced spin dephasing of a hole confined in a quasi-two-dimensional silicon quantum dot. Central to our treatment is accounting for higher-order corrections to the Luttinger Hamiltonian. Using experimentally reported parameters, we find that the new terms give rise to sweet-spots for the hole-spin dephasing, which are sensitive to device details: dot size and asymmetry, growth direction, and applied magnetic and electric fields. Furthermore, we estimate that the dephasing time at the sweet-spots is boosted by several orders of magnitude, up to order of milliseconds.

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Ognjen Malkoc, Peter Stano, Daniel Loss. 2022-01-17. Charge-noise induced dephasing in silicon hole-spin qubits. https://doi.org/10.1103/physrevlett.129.247701

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