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arXiv · 2205.01961

Model robustness for feedback stabilization of open quantum systems

Weichao Liang·Nina H. Amini
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Abstract

This paper generalizes the results in [30] concerning feedback stabilization of target states for N-level quantum angular momentum systems undergoing quantum non-demolition measurements (QND) in absence of the knowledge about initial states and parameters. Here we consider multiple measurement operators and study the stabilization toward a chosen target subspace which is a common eigenspace of measurement operators. Under the QND conditions, we show that this analysis provides necessary tools to ensure feedback stabilization based on a simplified filter whose state is a N-dimensional vector. A numerical analysis has been proposed in [18]. This paper provides a complete proof for the use of a simplified filter in feedback stabilization. This has important practical use as the dimension of quantum systems is usually high. This paper opens the way toward a complete proof concerning the robustness of a stabilizing feedback with respect to approximate filters, which is lacking.

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Weichao Liang, Nina H. Amini. 2022-07-28. Model robustness for feedback stabilization of open quantum systems. https://arxiv.org/abs/2205.01961

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