Extracting Quantum Many-body Scarred Eigenstates with Matrix Product States Institutional Repository Document uri icon

abstract

  • Quantum many-body scarred systems host nonthermal excited eigenstates immersed in a sea of thermal ones. In cases where exact expressions for these special eigenstates are not known, it is computationally demanding to distinguish them from their exponentially many thermal neighbors. We propose a matrix-product-state (MPS) algorithm, dubbed DMRG-S, to extract such states at system sizes far beyond the scope of exact diagonalization. Using this technique, we obtain scarred eigenstates in Rydberg-blockaded chains of up to 80 sites and perform a finite-size scaling study to address the lingering question of the stability for the N'eel state revivals in the thermodynamic limit. Our method also provides a systematic way to obtain exact MPS representations for scarred eigenstates near the target energy without a priori knowledge. In particular, we find several new scarred eigenstates with exact MPS representations in kinetically constrained spin and clock models.

author list (cited authors)

  • Zhang, S., Yuan, D., Iadecola, T., Xu, S., & Deng, D.

complete list of authors

  • Zhang, Shun-Yao||Yuan, Dong||Iadecola, Thomas||Xu, Shenglong||Deng, Dong-Ling

publication date

  • November 2022