Coherent dynamics of V-type systems driven by time-dependent incoherent radiation

Area of Science:

• Quantum Optics
• Physical Chemistry
• Spectroscopy

Background:

• Natural light-induced processes typically involve slowly increasing incoherent light.
• Understanding the dynamics of coherence under time-dependent excitation is crucial.
• V-type systems are fundamental models for studying light-matter interactions.

Purpose of the Study:

• To analytically solve the general case of time-dependent incoherent excitation for V-type systems.
• To investigate the disappearance of radiatively induced coherence with varying turn-on times.
• To determine the conditions under which Fano coherences are induced.

Main Methods:

• Development and application of a novel master equation method.
• Analytical solution for time-dependent incoherent excitation.
• Analysis of V-type quantum systems.

Main Results:

• Demonstrated the disappearance of radiatively induced coherence when radiation turn-on times exceed characteristic system times.
• Identified that natural timescales often lead to this coherence suppression for non-degenerate energy levels.
• Estimated that turn-on times slower than 1 ms induce Fano coherences only for energy eigenstates with separations < 0.9 cm^-1, in the absence of relaxation and decoherence.

Conclusions:

• The study provides a theoretical framework for understanding coherence dynamics under slow, incoherent light excitation.
• Findings highlight the importance of excitation timescale in controlling quantum coherence in V-type systems.
• The results have implications for controlling quantum phenomena in natural and artificial light-driven systems.