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No-Collapse Accurate Quantum Feedback Control via Conditional State Tomography
Sangkha Borah1,2,3, Bijita Sarma2,3
1Max Planck Institute for the Science of Light, Staudtstraße 2, 91058 Erlangen, Germany.
Physical Review Letters
|December 10, 2023
Summary
Measurement noise hinders quantum control. This study introduces conditional state tomography to enable noise-free quantum state monitoring, improving feedback control accuracy and enabling advanced reinforcement learning strategies.
Area of Science:
- Quantum physics
- Quantum control
- Information theory
Background:
- Measurement noise degrades the accuracy of quantum system state estimation.
- This limits the effectiveness of measurement-based feedback control protocols.
- Accurate inference of quantum dynamics is crucial for precise control.
Purpose of the Study:
- To develop a method for noise-free monitoring of quantum system dynamics.
- To enable precise measurement-based feedback control strategies.
- To enhance the capabilities of reinforcement learning in quantum control.
Main Methods:
- Real-time stochastic state estimation.
- Conditional state tomography for noise-free density matrix reconstruction.
- Utilizing single quantum trajectories for analysis.
Main Results:
- Demonstrated noise-free monitoring of conditional quantum dynamics.
- Enabled accurate estimation of the full density matrix from noisy measurements.
- Mitigated limitations imposed by measurement noise in quantum control.
Conclusions:
- Conditional state tomography effectively overcomes measurement noise challenges.
- This approach facilitates precise feedback control of quantum systems.
- The method significantly benefits reinforcement learning-based quantum control strategies.
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