



01416nas a2200133   4500008004100000245004200041210004200083260001500125490000600140520105200146100001901198700002801217856003701245       2018                        eng d00aResilience of scrambling measurements0 aResilience of scrambling measurements  c2018/06/180 vA3 a<p><span style="font-family: &quot;Lucida Grande&quot;, helvetica, arial, verdana, sans-serif; font-size: 14.4px;">Most experimental protocols for measuring scrambling require time evolution with a Hamiltonian and with the Hamiltonian&#39;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&#39;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.</span></p>1 aSwingle, Brian1 aHalpern, Nicole, Yunger  uhttps://arxiv.org/abs/1802.01587