Nonlinearities, or lack thereof, in single dot electric dipole spin resonance

Spin qubits in Si/SiGe require precise control of their physical state to be useful for practical quantum algorithms. An effective way to address individual spin qubits is by microwave-driven electric dipole spin resonance. The nonlinear effects [1] of microwave control pulses on the Rabi and Larmor frequencies have been observed but require a more comprehensive understanding. Here, we performed further studies of nonlinear effects in the presence of microwaves applied to a shared control line in a three qubit device. We also explored the effects of microwave heating and off-resonant drives during qubit operation. The results of this study allow us to further understand limiting factors on single qubit fidelities when scaling Si/SiGe spin qubits.

[1] Undseth et al., Phys. Rev. Appl. 19, 044078, (2023)