



01309nas a2200169   4500008004100000245003800041210003800079260001400117490000800131520085000139100001900989700002401008700002601032700002501058700001901083856003701102       2020                        eng d00aMinimal model for fast scrambling0 aMinimal model for fast scrambling  c9/22/20200 v1253 a<p>We study quantum information scrambling in spin models with both long-range all-to-all and short-range interactions. We argue that a simple global, spatially homogeneous interaction together with local chaotic dynamics is sufficient to give rise to fast scrambling, which describes the spread of quantum information over the entire system in a time that is logarithmic in the system size. This is illustrated in two exactly solvable models: (1) a random circuit with Haar random local unitaries and a global interaction and (2) a classical model of globally coupled non-linear oscillators. We use exact numerics to provide further evidence by studying the time evolution of an out-of-time-order correlator and entanglement entropy in spin chains of intermediate sizes. Our results can be verified with state-of-the-art quantum simulators.</p>1 aBelyansky, Ron1 aBienias, Przemyslaw1 aKharkov, Yaroslav, A.1 aGorshkov, Alexey, V.1 aSwingle, Brian  uhttps://arxiv.org/abs/2005.05362