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arXiv · 2411.01366

Electrical Interconnects for Silicon Spin Qubits

Christopher David White·Anthony Sigillito·Michael J. Gullans
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Abstract

Scalable spin qubit devices will likely require long-range qubit interconnects. We propose to create such an interconnect with a resistive topgate. The topgate is positively biased, to form a channel between the two dots; an end-to-end voltage difference across the nanowire results in an electric field that propels the electron from source dot to target dot. The electron is momentum-incoherent, but not necessarily spin-incoherent; we evaluate threats to spin coherence due to spin-orbit coupling, valley physics, and nuclear spin impurities. We find that spin-orbit coupling is the dominant threat, but momentum-space motional narrowing due to frequent scattering partially protects the electron, resulting in characteristic decoherence lengths ~15 mm for plausible parameters.

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Christopher David White, Anthony Sigillito, Michael J. Gullans. 2024-11-02. Electrical Interconnects for Silicon Spin Qubits. https://doi.org/10.1103/tmpl-pjvw

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