Dynamical Freezing and Emergent Floquet Conservation Laws
Arnab Das (IACS Kolkata)
A periodically driven quantum system with several degrees of freedom is naïvely expected to heat up indefinitely leading a locally infinite temperature -like state at long time. Here we show, a strong exception to this intuitive picture is observed if the drive strength crosses a threshold. Below the threshold, the expected Floquet Thermalization prevails, while above it, a set of approximate but perpetual conservation law emerge, fragmenting the Hilbert space stably into their eigensubspaces. This has been demonstrated for a large class of text book many-body systems including quantum Ising model of any dimension, and interaction distribution (including homogeneous), and any Heisenberg system, with strong manifestations in both finite and infinite systems. Here we will discuss the salient features of the phenomenology of Dynamical Freezing, and also review the marginal analytical understanding of the subject obtained so far.