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arXiv · 2605.12155

Optimal State Preparation for Impulse Estimation in Gaussian Quantum Systems

Kaspar Schmerling·Andreas Kugi·Andreas Deutschmann-Olek
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Abstract

We present an optimal control-based strategy to enhance the estimation of impulse-like disturbances in continuously monitored linear classical and quantum systems by exploiting non-equilibrium states. Using optimal estimation techniques for linear Gaussian systems to collect information from the temporal vicinity of the disturbance, we cast the minimization of disturbance estimation uncertainty as a nonlinear optimal control problem over time-dependent system parameters. The resulting method dynamically shapes the estimation covariances through parametric modulation, maximizing information gain at a known impulse time. This differs fundamentally from conventional squeezing protocols using periodic modulation that effectively degrade inference of impulse-like disturbances. Applied to nanomechanical resonators and levitated nanoparticles, optimal parametric driving reduces estimation variance by up to a factor of two relative to steady-state operation

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Kaspar Schmerling, Andreas Kugi, Andreas Deutschmann-Olek. 2026-05-12. Optimal State Preparation for Impulse Estimation in Gaussian Quantum Systems. https://arxiv.org/abs/2605.12155

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