Dynamics of Quantum Many-Body Scars on a Trapped-Ion Quantum Computer

Quantum Many-Body Scars (QMBS) represent a measure-zero set of non-thermal eigenstates defined by sub-volume law entanglement and the presence of dynamic fidelity revivals of certain initial states. Here we study this phenomenon by implementing a conditional mixed field Ising model [1] on a trapped-ion quantum computer. We prepare low-entangled states and a QMBS eigenstate using polynomial depth circuits following [2] on Quantinuum H-series hardware. We use this protocol to study key signatures of QMBS dynamics using the Loschmidt echo, spatiotemporal correlations of local observables, as well as their robustness to controlled perturbations of the model. 

 

[1] T. Iadecola and MS, “Quantum many-body scar states with emergent kinetic constraints and finite-entanglement revivals,” Phys. Rev. B 101, 024306 (2020). 

[2] E. J. Gustafson, A. C. Y. Li, A. Khan, J. Kim, D. M. Kurkcuoglu, M. S. Alam, P. P. Orth, A. Rahmani, and T. Iadecola, “Preparing quantum many-body scar states on quantum computers,” arXiv:2301.08226 (2023).