Hudomal, Ana - University of Leeds

Recent experiments have shown that preparing an array of Rydberg atoms in a certain initial state can lead to anomalously slow thermalization and persistent density oscillations [1]. This type of non-ergodic behavior has been attributed to the existence of “quantum many-body scars”, i.e., atypical eigenstates that have high overlaps with a small subset of vectors in the Hilbert space. Periodic dynamics and many-body scars are believed to originate from a “hard” kinetic constraint: due to strong interactions, two neighboring Rydberg atoms cannot be simultaneously excited. Here we propose a realization of quantum many-body scars in a 1D bosonic lattice model with a “soft” constraint in the form of density-assisted hopping [2]. We find that this model exhibits similar phenomenology to the Rydberg atom chain, including weakly entangled eigenstates at high energy densities and the presence of a large number of exact zero energy states, with distinct algebraic structure. We discuss the relation of this model to the standard Bose-Hubbard model and possible experimental realizations using ultracold atoms.

 

References:

[1] H. Bernien et al., Nature 551, 579 (2017).

[2] A. Hudomal, I. Vasic, N. Regnault, and Z. Papic, Commun. Phys. 3, 99 (2020).