We study one-dimensional spin-1/2 models in which strict confinement of Ising domain walls leads to the fragmentation of Hilbert space into exponentially many disconnected subspaces. Whereas most of the previous works emphasize dipole moment conservation as an essential ingredient for such fragmentation, we instead require two commuting U(1) conserved quantities associated with the total domain-wall number and the total magnetization. The latter arises naturally from the confinement of domain walls. Remarkably, while some connected components of the Hilbert space thermalize, others are integrable by Bethe ansatz. We further demonstrate how this Hilbert-space fragmentation pattern arises perturbatively in the confining limit of Z2 gauge theory coupled to fermionic matter, leading to a hierarchy of time scales for motion of the fermions. This model can be realized experimentally in two complementary settings.

%B Phys. Rev. Lett. %V 124 %8 5/22/2020 %G eng %U https://arxiv.org/abs/1912.04300 %N 207602 %R https://doi.org/10.1103/PhysRevLett.124.207602 %0 Journal Article %D 2020 %T Quench Dynamics of a Fermi Gas with Strong Long-Range Interactions %A Elmer Guardado-Sanchez %A Benjamin M. Spar %A Peter Schauss %A Ron Belyansky %A Jeremy T. Young %A Przemyslaw Bienias %A Alexey V. Gorshkov %A Thomas Iadecola %A Waseem S. Bakr %XWe induce strong non-local interactions in a 2D Fermi gas in an optical lattice using Rydberg dressing. The system is approximately described by a t−V model on a square lattice where the fermions experience isotropic nearest-neighbor interactions and are free to hop only along one direction. We measure the interactions using many-body Ramsey interferometry and study the lifetime of the gas in the presence of tunneling, finding that tunneling does not reduce the lifetime. To probe the interplay of non-local interactions with tunneling, we investigate the short-time relaxation dynamics of charge density waves in the gas. We find that strong nearest-neighbor interactions slow down the relaxation. Our work opens the door for quantum simulations of systems with strong non-local interactions such as extended Fermi-Hubbard models.

%8 10/12/2020 %G eng %U https://arxiv.org/abs/2010.05871