Efficient post-selection in light cone correlations of monitored quantum circuits

Li, Jimin; Jack, Robert L; Bertini, Bruno; Garrahan, Juan P

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.

Citation

Li, J., Jack, R. L., Bertini, B., & Garrahan, J. P. (2025). Efficient post-selection in light cone correlations of monitored quantum circuits. Physical Review B, 111(2), Article 024309. https://doi.org/10.1103/physrevb.111.024309

• Journal Article Type: Article
• Acceptance Date: Dec 24, 2024
• Online Publication Date: Jan 21, 2025
• Publication Date: Jan 21, 2025
• Deposit Date: Jan 22, 2025
• Publicly Available Date: Jan 22, 2025
• Journal: Physical Review B
• Print ISSN: 2469-9950
• Electronic ISSN: 2469-9969
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 111
• Issue: 2
• Article Number: 024309
• DOI: https://doi.org/10.1103/physrevb.111.024309
• Keywords: Open quantum systems & decoherence; Quantum circuits'; Quantum correlations in quantum information; Quantum measurements; Large deviation & rare event statistics; Tensor network methods
• Public URL: https://nottingham-repository.worktribe.com/output/44425032
• Publisher URL: https://journals.aps.org/prb/abstract/10.1103/PhysRevB.111.024309