Optimized driving of superconducting artificial atoms for improved single-qubit gates

We employ simultaneous shaping of in-phase and out-of-phase resonant microwave drives to reduce single-qubit gate errors arising from the weak anharmonicity of transmon superconducting artificial atoms. To reduce the effect of higher levels present in the transmon spectrum, we apply Gaussian and derivative-of-Gaussian envelopes to the in-phase and out-of-phase quadratures, respectively, and optimize over their relative amplitude. Using randomized benchmarking, we obtain a minimum average error per gate of 0.007 +/- 0.005 using 4-ns-wide pulses, which is limited by decoherence. This simple optimization technique works for multiple transmons coupled to a single microwave resonator in a quantum bus architecture.