Resilience of scrambling measurements
Abstract
Most experimental protocols for measuring scrambling require time evolution with a Hamiltonian and with the Hamiltonian's negative counterpart (backwards time evolution). Engineering controllable quantum many-body systems for which such forward and backward evolution is possible is a significant experimental challenge. Furthermore, if the system of interest is quantum-chaotic, one might worry that any small errors in the time reversal will be rapidly amplified, obscuring the physics of scrambling. This paper undermines this expectation: We exhibit a renormalization protocol that extracts nearly ideal out-of-time-ordered-correlator measurements from imperfect experimental measurements. We analytically and numerically demonstrate the protocol's effectiveness, up to the scrambling time, in a variety of models and for sizable imperfections. The scheme extends to errors from decoherence by an environment.
Keywords
Cite
@article{arxiv.1802.01587,
title = {Resilience of scrambling measurements},
author = {Brian Swingle and Nicole Yunger Halpern},
journal= {arXiv preprint arXiv:1802.01587},
year = {2018}
}
Comments
14 pages (24 figures) + appendices. Close to published version. Added holographic calculation, compressed other information