Exponential speedup in measuring out-of-time-ordered correlators with a single bit of quantum information
arXiv:2009.03415 · doi:10.1016/j.physleta.2021.127257
Abstract
Out-of-time-ordered correlators (OTOC) are a quantifier of quantum information scrambling and quantum chaos. We propose an efficient quantum algorithm to measure OTOCs that provides an exponential speed-up over the best known classical algorithm provided the OTOC operator to be estimated admits an efficient gate decomposition. We also discuss a scheme to obtain information about the eigenvalue spectrum and the spectral density of OTOCs.
5 pages