Non-Markovian noise presents a particularly relevant challenge in understanding and combating decoherence in quantum computers, yet is challenging to capture in terms of simple models. Here we show that a simple phenomenological dynamical model known as the post-Markovian master equation (PMME) accurately captures and predicts non-Markovian noise in a superconducting qubit system. The PMME is constructed using experimentally measured state dynamics of an IBM Quantum Experience cloud-based quantum processor, and the model thus constructed successfully predicts the non-Markovian dynamics observed in later experiments. The model also allows the extraction of information about cross-talk and measures of non-Markovianity. We demonstrate definitively that the PMME model predicts subsequent dynamics of the processor better than the standard Markovian master equation.
@article{arxiv.2111.07051,
title = {Predicting non-Markovian superconducting qubit dynamics from tomographic reconstruction},
author = {Haimeng Zhang and Bibek Pokharel and E. M. Levenson-Falk and Daniel Lidar},
journal= {arXiv preprint arXiv:2111.07051},
year = {2022}
}