Online Parameter Estimation for Continuously Monitored Quantum Systems

• URL: http://arxiv.org/abs/2403.04648v2
• Date: Tue, 18 Jun 2024 08:36:43 GMT
• Title: Online Parameter Estimation for Continuously Monitored Quantum Systems
• Authors: Henrik Glavind Clausen, Pierre Rouchon, Rafal Wisniewski,
• Abstract summary: We consider the problem of online (real-time, single-shot) estimation of static or slow-varying parameters along quantum trajectories in quantum dynamical systems. We formulate an algorithm for computing the maximum estimate of unknown parameters using an approach based on a gradient on the log-likelihood function.
• Score: 0.6554326244334868
• License: http://creativecommons.org/licenses/by-nc-nd/4.0/
• 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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