Detail
Superconducting readout was drifting under drive noise and crosstalk, so we designed a geometric-phase gate that keeps discrimination fidelity stable. Steering the Bloch vector along a calibrated loop accumulates phase that separates ground and excited populations more cleanly than square-pulse discrimination.
Simulations and measurements cover simultaneous readout scenarios where crosstalk usually erodes fidelity. The geometric path, paired with simple amplitude rebalancing, maintains separation even when neighboring qubits are driven off-axis.
We compare against a square-pulse baseline, showing robustness to amplitude and phase noise. The talk includes bias-point tuning rules, a lightweight calibration sequence, and error budgets that explain when geometric control is worth the overhead.