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arXiv · 2403.04648

Online Parameter Estimation for Continuously Monitored Quantum Systems

Henrik Glavind Clausen·Pierre Rouchon·Rafal Wisniewski
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Abstract

In this work, we consider the problem of online (real-time, single-shot) estimation of static or slow-varying parameters along quantum trajectories in quantum dynamical systems. Based on the measurement signal of a continuously-monitored quantum system, we propose a recursive algorithm for computing the maximum likelihood estimate of unknown parameters using an approach based on stochastic gradient ascent on the log-likelihood function. We formulate the algorithm in both discrete-time and continuous-time and illustrate the performance of the algorithm through simulations of a simple two-level system undergoing homodyne measurement from which we are able to track multiple parameters simultaneously.

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Henrik Glavind Clausen, Pierre Rouchon, Rafal Wisniewski. 2024-03-07. Online Parameter Estimation for Continuously Monitored Quantum Systems. https://doi.org/10.1109/lcsys.2024.3407608

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