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arXiv · 2408.14422

Using a high-fidelity numerical model to infer the shape of a few-hole Ge quantum dot

Mitchell Brickson·N. Tobias Jacobson·Andrew J. Miller·Leon N. Maurer·Tzu-Ming Lu·Dwight R. Luhman·Andrew D. Baczewski
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Abstract

The magnetic properties of hole quantum dots in Ge are sensitive to their shape due to the interplay between strong spin-orbit coupling and confinement. We show that the split-off band, surrounding SiGe layers, and hole-hole interactions have a strong influence on calculations of the effective $g$ factor of a lithographic quantum dot in a Ge/SiGe heterostructure. Comparing predictions from a model including these effects to raw magnetospectroscopy data, we apply maximum-likelihood estimation to infer the shape of a quantum dot with up to four holes. We expect that methods like this will be useful in assessing qubit-to-qubit variability critical to further scaling quantum computing technologies based on spins in semiconductors.

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Mitchell Brickson, N. Tobias Jacobson, Andrew J. Miller, Leon N. Maurer, Tzu-Ming Lu, Dwight R. Luhman, Andrew D. Baczewski. 2024-08-26. Using a high-fidelity numerical model to infer the shape of a few-hole Ge quantum dot. https://arxiv.org/abs/2408.14422

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