Abstract

Recent experiments on large chains of Rydberg atoms [H. Bernien et al., Nature 551, 579 (2017)] have demonstrated the possibility of realizing 1D systems with locally constrained Hilbert spaces, along with some surprising signatures of non-ergodic dynamics, such as persistent oscillations following a quench from the Néel product state. In this talk we will argue that this phenomenon is a manifestation of a “quantum many-body scar”, i.e., a concentration of extensively many eigenstates of the system around special many-body states [1]. The special states are analogs of unstable classical periodic orbits in the single-particle quantum billiards. I will present a model based on a single particle hopping on the Hilbert space graph, which quantitatively captures the scarred wave functions up to large systems of 32 atoms. These results suggest that scarred many-body bands give rise to a new universality class of quantum dynamics, which opens up opportunities for creating and manipulating novel states with long-lived coherence in systems that are now amenable to experimental study.

[1] C. J. Turner, A. A. Michailidis, D. A. Abanin, M. Serbyn, Z. Papić, Nat. Phys, 14, 745 (2018).