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arXiv · 2508.21790

Experimental measurement of quantum first-passage-time distributions

Joseph M. Ryan·Simon Gorbaty·Thomas J. Kessler·Mitchell G. Peaks·Stephen W. Teitsworth·Crystal Noel
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Abstract

Classical First-Passage-Time Distributions (FPTDs) have been extensively studied both theoretically and experimentally. Their quantum counterparts-Quantum First-Passage-Time Distributions (QFPTDs)-remain largely unexplored and have deep implications for both fundamental physics and the development of emerging quantum technologies. We measure the first QFPTDs using a motional mode of a single trapped ion. We develop a novel composite-phase laser pulse sequence to perform tunable stroboscopic single-shot projective measurements of the motional state of a trapped ion. We measure QFPTDs of the ion energy when coupled to electric-field noise. The measurement protocol developed here is broadly applicable to other quantum systems and provides a powerful method for exploring a broad range of QFPTD phenomena. With these results we open a new field of experimental investigations of QFPT processes with potential future relevance to quantum search algorithms, unraveling connections between classical and quantum dynamics, and study of the quantum measurement problem.

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Joseph M. Ryan, Simon Gorbaty, Thomas J. Kessler, Mitchell G. Peaks, Stephen W. Teitsworth, Crystal Noel. 2025-08-29. Experimental measurement of quantum first-passage-time distributions. https://doi.org/10.1103/p3pl-1m6n

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