We introduce a novel protocol, which enables Heisenberg-limited quantum-enhanced sensing using the dynamics of any interacting many-body Hamiltonian. Our approach - dubbed butterfly metrology - utilizes a single application of forward and reverse time evolution to produce a coherent superposition of a "scrambled" and "unscrambled" quantum state. In this way, we create metrologically-useful long-range entanglement from generic local quantum interactions. The sensitivity of butterfly metrology is given by a sum of local out-of-time-order correlators (OTOCs) - the prototypical diagnostic of quantum information scrambling. Our approach broadens the landscape of platforms capable of performing quantum-enhanced metrology; as an example, we provide detailed blueprints and numerical studies demonstrating a route to scalable quantum-enhanced sensing in ensembles of solid-state spin defects.
@article{arxiv.2411.12794,
title = {A Universal Protocol for Quantum-Enhanced Sensing via Information Scrambling},
author = {Bryce Kobrin and Thomas Schuster and Maxwell Block and Weijie Wu and Bradley Mitchell and Emily Davis and Norman Y. Yao},
journal= {arXiv preprint arXiv:2411.12794},
year = {2024}
}