Enabling modularity for spin qubits via driven control and enhanced-range coupling

Modular spin-based quantum information processing represents a promising path to scaling but requires coherent and tunable control and entanglement of spin qubits over a wide range of distances. While the exchange interaction enables rapid gates and coherence-protected qubit encodings with all-electrical control in this platform, the inherently short range of the interaction imposes constraints on the ultimate scalability of both the qubits and their associated control electronics. To address these challenges, we theoretically investigate quantum dot spin qubit modules that combine the increased flexibility enabled by electrical driving [1] with the enhanced range of spin-mediated and photon-mediated entangling interactions. We identify optimal operation regimes for integrating drive-based control with entanglement between spatially separated spin qubits. Our work suggests a promising route to scalability for spin-based quantum processors via modularity.

[1] V. Srinivasa, J. M. Taylor, and J. R. Petta, PRX Quantum 5, 020339 (2024).