Charge-insensitive single-atom spin-orbit qubit in silicon

TL;DR

This paper proposes a silicon-based acceptor spin-orbit qubit that is resistant to electrical noise, enabling long-range entanglement and high-fidelity quantum operations suitable for scalable quantum computing.

Contribution

It introduces a novel acceptor-based spin-orbit qubit in silicon that operates at a noise-insensitive sweet spot, facilitating long-range entanglement and quantum gate operations.

Findings

Long qubit lifetime enabling over 10^5 single-qubit gates

Dipole-dipole mediated two-qubit gates exceeding 10^4

Feasibility of circuit QED with single spins including readout and entanglement

Abstract

High fidelity entanglement of an on-chip array of spin qubits poses many challenges. Spin-orbit coupling (SOC) can ease some of these challenges by enabling long-ranged entanglement via electric dipole-dipole interactions, microwave photons, or phonons. However, SOC exposes conventional spin qubits to decoherence from electrical noise. Here we propose an acceptor-based spin-orbit qubit in silicon offering long-range entanglement at a sweet spot where the qubit is protected from electrical noise. The qubit relies on quadrupolar SOC with the interface and gate potentials. As required for surface codes, $10^5$ electrically mediated single-qubit and $10^4$ dipole-dipole mediated two-qubit gates are possible in the predicted spin lifetime. Moreover, circuit quantum electrodynamics with single spins is feasible, including dispersive readout, cavity-mediated entanglement, and spin-photon entanglement. An industrially relevant silicon-based platform is employed.