Nonlinear Response and Crosstalk of Electrically Driven Silicon Spin Qubits

Micromagnet-based electric dipole spin resonance offers an attractive path for the near-term scaling of dense arrays of silicon spin qubits in gate-defined quantum dots while maintaining long coherence times and high control fidelities. However, accurately controlling dense arrays of qubits using a multiplexed drive will require an understanding of the cross-talk mechanisms that may reduce operational fidelity. We identify an unexpected cross-talk mechanism whereby the Rabi frequency of a driven qubit is drastically changed when the drive of an adjacent qubit is turned on. These observations raise important considerations for scaling single-qubit control.

Automated summary

Micromagnet-based electric dipole spin resonance is a promising method for scaling silicon spin qubits in gate-defined quantum dots, while maintaining long coherence times and high control fidelities. However, understanding and mitigating cross-talk mechanisms is crucial for accurately controlling dense arrays of qubits using a multiplexed drive. We identified an unexpected cross-talk mechanism where the Rabi frequency of a driven qubit is significantly affected by the drive of an adjacent qubit. These findings have important implications for scaling single-qubit control.