IQI Weekly Seminar
Abstract: We study in detail the properties of the quantum East model, an interacting quantum spin chain inspired by simple kinetically constrained models of classical glasses.
Through a combination of analytics, exact diagonalization and tensor network methods we show the existence of a fast-to-slow transition throughout the spectrum that follows from a localization transition in the ground state.
On the slow side, we explicitly construct a large (exponential in size) number of non-thermal states which become exact finite-energy-density eigenstates in the large size limit,
as expected for a true phase transition.
A ``super-spin'' generalization allows us to find a further large class of area-law states proved to display very slow relaxation.
Under slow conditions, many eigenstates have a large overlap with product states and can be approximated well by matrix product states at arbitrary energy densities.
We discuss implications of our results for slow thermalization and non-ergodicity more generally for quantum East-type Hamiltonians and their extension in two or higher dimensions.