Design of a Discrete-Time Fault-Tolerant Quantum Filter and Fault Detector

Area of Science:

• Quantum Information Science
• Quantum Optics
• Control Theory

Background:

• Open quantum systems are susceptible to environmental noise and operational faults.
• Accurate state estimation is crucial for controlling quantum systems like laser-atom interactions.
• Stochastic faults in quantum systems can degrade performance and lead to errors.

Purpose of the Study:

• To develop a discrete-time fault-tolerant quantum filtering method.
• To address stochastic faults in laser-atom open quantum systems.
• To achieve simultaneous optimal estimation of atomic observables and fault processes.

Main Methods:

• Utilizing discrete-time quantum measurements.
• Formulating recursive quantum stochastic difference equations.
• Applying the filtering approach to a dispersive interaction quantum system model.

Main Results:

• Optimal estimates of atomic observables are obtained.
• The classical fault process is simultaneously estimated.
• The proposed filtering approach is demonstrated effectively.

Conclusions:

• The developed quantum filter provides robust state estimation under stochastic faults.
• The method allows for real-time monitoring and correction of system behavior.
• This work contributes to the advancement of fault-tolerant quantum control.