quantum information

Noise-resilient and Scalable Quantum Error Correction for Nuclear Spin Qubits in Silicon with Electron Shuttling

arXiv:2607.27527

summary

The paper proposes electron pair interferometry (EPI) to enable robust control and measurement of nuclear spin qubits in silicon, using shuttled electron pairs to transfer nuclear parity and implement a universal gate set suitable for CSS quantum error correction with low sensitivity to charge noise.

Abstract

Nuclear spin qubits in silicon are well-isolated from their environment. Consequently, they have very long lifetimes and low sensitivity to noise, but this also suggests that control and measurement is challenging. We introduce electron pair interferometry (EPI), a protocol to overcome this challenge and maintain robustness to noise. EPI is implemented using an array of quantum dots with isoelectronic nuclear spin qubits located in the dots. A pair of electrons are initialized into a singlet ground state, split apart, and shuttled to the dots containing nuclear spin qubits. We show it is possible to coherently transfer the parity of the nuclei onto the measurable state of singlet/triplet-encoded electrons. Global nuclear magnetic resonance (NMR) can be used to change bases and implement dynamical decoupling (DD). Combined with selective hyperfine-induced rotations, our gate set is complete for universal quantum computation, tailored to Calderbank-Shor-Steane (CSS) quantum error correction, and robust to noise. We discuss very low sensitivity to charge noise and study the sensitivity to both DC and AC magnetic field inhomogeneity which depends strongly on their relative strengths.

9 pages, 3 figures

Topics & keywords

#nuclear spin qubits#silicon quantum dots#electron shuttling#quantum error correction#electron pair interferometry#dynamical decouplinghyperfine interactionsinglet-triplet encodingCSS codescharge noise resilienceglobal NMR controlmagnetic field inhomogeneity