Incoherent control of locally controllable quantum systems

Area of Science:

• Quantum mechanics
• Quantum control theory
• Atomic physics

Background:

• Controlling quantum systems is crucial for quantum technologies.
• Existing methods often require full system controllability.
• Locally controllable systems present unique challenges.

Purpose of the Study:

• To propose a novel incoherent control scheme for quantum systems with partial controllability.
• To demonstrate the effectiveness of projective measurements in quantum state control.
• To establish a link between control design and controllability analysis.

Main Methods:

• Amplitude amplification of the initial quantum state using unitary transformations.
• Projective measurement to collapse the state into a desired eigenstate.
• Unitary controlled transformation for final state optimization.
• Development of two control algorithms for different quantum system classes.

Main Results:

• The proposed scheme effectively controls quantum states in locally controllable systems.
• Projective measurements are shown to be a viable control mechanism.
• Application to a hydrogen atom in an external field validates the approach.
• Demonstrated utility of local controllability information in designing control laws.

Conclusions:

• Incoherent control offers an effective engineering approach for quantum systems.
• Projective measurements can be utilized as a powerful control tool.
• The scheme bridges control design and controllability analysis for quantum systems.