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Title: Benchmarking quantum simulators using ergodic quantum dynamics
We propose and analyze a sample-efficient protocol to estimate the fidelity between an experimentally prepared state and an ideal target state, applicable to a wide class of analog quantum simulators without advanced spatiotemporal control. Our protocol relies on universal fluctuations emerging from generic Hamiltonian dynamics, that we discover in the present work. It does not require fine-tuned control over state preparation, quantum evolution, or readout capability, while achieving near optimal sample complexity: a percent-level precision is obtained with ∼ 103 measurements, independent of system size. Furthermore, the accuracy of our fidelity estimation improves exponentially with increasing system size. We numerically demonstrate our protocol in a variety of quantum simulator platforms including quantum gas microscopes, trapped ions, and Rydberg atom arrays. We discuss applications of our method for tasks such as multi-parameter estimation of quantum states and processes.  more » « less
Award ID(s):
1753386
PAR ID:
10561430
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
ARXIV
Date Published:
Journal Name:
Physical Review Letters
ISSN:
2205-12211
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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