Coherent dynamics in chaotic spin chains via interference-protected subspaces (opens in new tab)

Generic quantum many-body systems are expected to thermalize, scrambling initial coherence while local observables relax to equilibrium values. Weak ergodicity breaking, often associated with quantum many-body scarring of homogeneous states, provides rare exceptions with long-lived coherence. We introduce a family of local spin-1/2 chains with a structured subspace that hosts a much broader range of nonthermal phenomena, such as scars, chirally ...