Topological Quantum Many-Body Scars in Quantum Dimer Models

We construct two-dimensional lattice models with quantum dimer degrees of freedom that violate the eigenstate thermalization hypothesis (ETH) by featuring quantum many-body scars in their excitation spectrum. These scars consist of single exactly known excited eigenstates with atypical (area law) entanglement entropy. We explicitly construct such models for the kagome and checkerboard lattices. We compute entanglement entropy numerically for the surrounding states, and analytically for the scar states themselves. Furthermore, we corroborate the non-integrable nature of these quantum dimer models by studying the statistics of the spacings between consecutive energy levels.