Characterization of Transmon Qubit Gate Operations based on Time-dependent Simulations with Realistic Noise*

Fault tolerant quantum computation requires improving scalable control protocols for specific qubit implementations to mitigate noise-induced error. Simulations that accurately capture observed physical qubit behavior while scaling to multi-qubit circuit models provide a useful tool to address this challenge. We present results on time-dependent simulations of coupled transmon qubits. The model captures driven multi-level dynamics in and out of the computational subspace. Noise incorporated into the model includes fast and slow dephasing, excited-state decay, timing jitter, and phase noise. Process tomography of gates including these noise sources goes beyond standard models that typically make simplifying assumptions about the noise. This will enable analysis of small circuit encodings of quantum error correction and algorithms being proposed as demonstrations on near-term qubit devices.