Feedback control Archives - IEEE Transactions on Quantum Engineering

Automated Active-Visibility-Control Loop for Stabilized DPS-QKD Decoding under Dynamic Wavelength Drift

July 10, 2026Kuan-Wei Hu, Chih-Hsien Cheng, Atsushi Matsumoto, Kouichi Akahane, Gong-Ru LinEarly Access, Open AccessAlgorithms, Automatic voltage control, Codes, Current, Decoding, Feedback, Feedback control, Single-photon avalanche diodes, Temperature, Timing

Abstract: Automated and instantaneous stabilizing control of the quantum key decoder is the mandatory procedure, which guarantees real-time and high-speed differential-phase-shift (DPS) quantum key distribution (QKD) at low erroneous rate, and ensures the delay-line interferometric (DLI) decoding of the weak-coherent-pulse quantum bit-stream at a qualified and constant visibility. As the QKD system often suffers from […]

Robust H∞ Uncertainties-Tolerant Observer-Based Reference Quantum Trajectory Tracking Control for Lindblad Master Equation

December 18, 2025Shin-Yi Wen Bor-Sen Chen Chun-Liang LinEnabling TechnologiesControl design, Estimation, Feedback control, Mathematical models, Optimization, Pollution measurement, Quantum state, Quantum system, Trajectory, Trajectory tracking

Abstract: In this article, a robust output feedback reference quantum trajectory tracking control design is proposed through the simultaneous continuous weak measurement of noncommuting observables. Using the robust H∞ uncertainties-tolerant observer-based reference quantum trajectory tracking control (UTOBRQTTC) design strategy, the proposed method can robustly estimate the quantum trajectory and robustly track a sequence of any […]

Fast State Stabilization Using Deep Reinforcement Learning for Measurement-Based Quantum Feedback Control

September 4, 2025Chunxiang Song Yanan Liu Daoyi Dong Hidehiro YonezawaQuantum ComputingConvergence, Current measurement, Deep Reinforcement Learning, Feedback control, Quantum computing, Quantum entanglement, Quantum state, Quantum system, Trajectory, Velocity measurement

Abstract: The stabilization of quantum states is a fundamental problem for realizing various quantum technologies. Measurement-based-feedback strategies have demonstrated powerful performance, and the construction of quantum control signals using measurement information has attracted great interest. However, the interaction between quantum systems and the environment is inevitable, especially when measurements are introduced, which leads to decoherence. […]