Charge noise arising from two-level fluctuators is considered to play a key role in causing qubit frequency shifts in silicon spin qubits, resulting in deteriorated gate fidelity. Higher temperatures can improve gate fidelity, but the microscopic origins of this effect and of qubit frequency shift have not yet been established. Now, using statistical simulations, researchers have clarified the parameter regimes under which gate fidelity can be improved and the potential origin of qubit frequency shifts.

Researchers identified mechanisms that cause frequency shifts in silicon spin qubits and improvements of operating at 200 millikelvin.

Charge noise arising from two-level fluctuators is considered to play a key role in causing qubit frequency shifts in silicon spin qubits, resulting in deteriorated gate fidelity.…