A solvable quantum circuit’s limits define chaos

Researchers Samuel H. Pickering and Bruno Bertini introduced a family of quantum circuits that exhibit a surprising hybrid behavior. Their dynamics are solvable only for sufficiently long times, behaving chaotically on shorter timescales. This means the circuits offer a way to study typically inaccessible chaotic quantum systems by using solvable models, while still imposing constraints on generated correlations. “Solvability does not prevent the generation of chaotic dynamics,” the researchers write, but it does affect correlations beyond a tunable threshold. The work uses a method within the circuits to provide analytical results for the early, non-solvable time regime, complementing numerical experiments. The newly designed circuits exhibit a surprising temporal characteristic. Their solvability is limited to correlations extending beyond a specific, adjustable distance threshold. This means that within a shorter range, the circuits behave chaotically, demonstrating a hybrid dynamic not previously observed in quantum systems. Researchers detail that the circuits’ ability to transition between solvable and generic behavior is a key feature, allowing for the study of complex quantum dynamics…