High-fidelity two-qubit entanglement operations pose new challenges for spin qubits. Although spin orbit-coupling (SOC) can simplify entanglement via electric fields and microwave photons, it exposes conventional spin qubits to electrical noise. Here we devise a gate-tunable single-acceptor spin-orbit qubit in silicon having a sweet spot where the electric dipole spin resonance (EDSR) is maximized, and the qubit is simultaneously insensitive to dephasing from low-frequency electrical noise. The sweet spot protects the qubit during rapid single-qubit EDSR and two-qubit dipole-dipole mediated operations, and is only obtained by treating SOC non-perturbatively. More than 10000 one-qubit and 1000 two-qubit operations are possible in the predicted relaxation time, as necessary for surface codes. Moreover, circuit quantum electrodynamics with single dopants is feasible in this scheme, including dispersive single-spin readout, cavity-mediated two-qubit entangement, and strong Jaynes-Cummings coupling. Our approach provides a scalable route for controlling electrical and photon-mediated interactions between spins of individual dopants in silicon.
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