Measuring out-of-time-ordered correlation functions without reversing time evolution
Abstract
Out-of-time-ordered correlation functions (OTOCs) play a crucial role in the study of thermalization, entanglement, and quantum chaos, as they quantify the scrambling of quantum information due to complex interactions. As a consequence of their out-of-time-ordered nature, OTOCs are difficult to measure experimentally. Here we propose an OTOC measurement protocol that does not rely on the reversal of time evolution and is easy to implement in a range of experimental settings. The protocol accounts for both pure and mixed initial states, and is applicable to systems that interact with environmental degrees of freedom. We demonstrate the application of our protocol by the characterization of scrambling in a periodically-driven spin that exhibits quantum chaos.
Cite
@article{arxiv.2003.03980,
title = {Measuring out-of-time-ordered correlation functions without reversing time evolution},
author = {Philip Daniel Blocher and Serwan Asaad and Vincent Mourik and Mark A. I. Johnson and Andrea Morello and Klaus Mølmer},
journal= {arXiv preprint arXiv:2003.03980},
year = {2022}
}
Comments
12 pages, 6 figures. Updated figure labels and author affiliation. Made a few minor edits to the main text