Quantum dynamics driven by continuous laser fields under measurements: towards measurement-assisted quantum dynamics...

Area of Science:

• Quantum mechanics
• Quantum optics
• Quantum information science

Background:

• Understanding quantum system dynamics under continuous measurement is crucial.
• Laser-driven systems exhibit complex behaviors influenced by external fields.
• The impact of measurement on quantum coherence and population dynamics requires detailed investigation.

Purpose of the Study:

• To develop a theoretical framework for analyzing quantum system dynamics under continuous measurement.
• To investigate how quantum measurements affect coherent population dynamics driven by laser fields.
• To explore the potential of measurement-assisted quantum control.

Main Methods:

• Definition of a superoperator to account for system transitions due to measurement.
• Derivation of an effective Liouvillian governing incoherent population dynamics under frequent measurements.
• Application of the formulation to two-level and Lambda-type three-level systems.

Main Results:

• Quantum system dynamics become frozen in the frequent measurement limit.
• The space spanned by unmeasured states becomes isolated from the original system.
• Quantum measurements were shown to hinder coherent population dynamics in specific systems.

Conclusions:

• The developed superoperator effectively describes measurement-induced transitions.
• Frequent quantum measurements can lead to frozen dynamics and isolated subspaces.
• Analysis suggests that quantum control can be achieved by assisting quantum measurements.