Quantum Feedback Cooling without State Filtering

• URL: http://arxiv.org/abs/2603.06370v1
• Date: Fri, 06 Mar 2026 15:23:03 GMT
• Title: Quantum Feedback Cooling without State Filtering
• Abstract summary: We introduce a state-based feedback law that stabilizes quantum states or subspaces associated with extremal values of a continuously monitored observable.<n>We then propose an output-based approximation that uses simple filtering of the measurement record to emulate the required feedback signal.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• 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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