Efficient post-selection in light-cone correlations of monitored quantum circuits
Abstract
We consider how to target evolution conditioned on atypical measurement outcomes in monitored quantum circuits, i.e., the post-selection problem. We show that for a simple class of measurement schemes, post-selected light-cone dynamical correlation functions can be obtained efficiently from the averaged correlations of a different unitary circuit. This connects rare measurement outcomes in one circuit to typical outcomes in another one. We derive conditions for the existence of this rare-to-typical mapping in brickwork quantum circuits made of XYZ gates. We illustrate these general results with a model system that exhibits a dynamical crossover (a smoothed dynamical transition) in event statistics, and discuss extensions to more general dynamical correlations.
Keywords
Cite
@article{arxiv.2408.13096,
title = {Efficient post-selection in light-cone correlations of monitored quantum circuits},
author = {Jimin Li and Robert L. Jack and Bruno Bertini and Juan P. Garrahan},
journal= {arXiv preprint arXiv:2408.13096},
year = {2025}
}