2019: A Hilbert Space Odyssey into the characterization of two-qubit gates using phase estimation

Fast and accurate gate calibration is necessary for quantum computing. Process tomography is inaccurate, in part because of SPAM. Procedures like Gate Set tomography are accurate but too slow. In this talk we present protocols that allow you to robustly tune up arbitrary two qubit gates with high accuracy. We generalize iterative phase and Hamiltonian estimation procedures developed for single qubits to two qubit gates. The resulting protocol has Heisenberg limited scaling when estimating any of the gate parameters. We present results from an experimental demonstration of the protocol run through the full stack at Rigetti Computing.