Digital quantum simulation, learning of the Floquet Hamiltonian, and quantum chaos of the kicked top

Abstract The kicked top is one of the paradigmatic models in study quantum chaos (Haake et al 2018 Quantum Signatures Chaos ( Springer Series Synergetics vol 54 )). Recently it has been shown that onset can be related to proliferation Trotter errors digital simulation (DQS) collective spin systems. Specifically, becomes manifest expectation values few-body observables strongly deviating from target dynamics above a critical step, where spectral statistics Floquet operator predicted by random matrix theory. In this work, we these phenomena framework Hamiltonian learning (HL). We show how recently developed HL protocol employed reconstruct generator stroboscopic dynamics, i.e., Hamiltonian, top. further revealed as transition regime which cannot approximately described low-order truncation Floquet–Magnus expansion. This opens up new experimental possibilities for analysis on level implemented generalized DQS many-body systems scalable way. paper memory our colleague and friend Fritz Haake.