General Algorithms for SPAM Noise Characterization

Abhijith Jayakumar, Stefano Chessa, Carleton Coffrin, Andrey Y. Lokhov, Marc Vuffray, Sidhant Misra

Abstract: We present a general denoising algorithm for characterizing state preparation and measurement (SPAM) errors. This algorithm works by constructing a set of canonical super-operators using a set of efficient unitary circuits. This allows us to completely estimate the state and noise in the measurement apparatus up to the unavoidable “blame” gauge. We also show how this blame gauge can be fixed given prior information about the system, like the purity of the original state and independence properties of detector noise.