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arXiv · 2603.06370

Quantum Feedback Cooling without State Filtering

Lorenzo Franceschetti·Francesco Ticozzi
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Abstract

We introduce a state-based feedback law that stabilizes quantum states or subspaces associated with extremal values of a continuously monitored observable - a problem motivated by quantum cooling tasks. We then propose an output-based approximation that uses simple filtering of the measurement record to emulate the required feedback signal, thereby avoiding full real-time quantum state estimation, a key bottleneck for implementing and scaling filtering-based feedback control. The performance of the resulting strategy is demonstrated numerically on two test-bed models for feedback cooling.

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Lorenzo Franceschetti, Francesco Ticozzi. 2026-03-06. Quantum Feedback Cooling without State Filtering. https://arxiv.org/abs/2603.06370

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