Simulation of Interaction of Oriented J Aggregates with Resonance Laser Radiation

TL;DR

This paper presents a theoretical and numerical study of how laser radiation interacts with J aggregates of cyanine dyes, revealing phenomena like bistability and solitons under certain conditions.

Contribution

It introduces a quantum mechanical model incorporating relaxation, annihilation, and broadening effects to analyze laser interactions with J aggregates.

Findings

Existence of spatial bistability and molecular switching waves.

Demonstration of dissipative solitons in the system.

Analysis of inhomogeneous broadening effects on coherence length.

Abstract

The interaction of laser radiation with single J aggregates of cyanine dyes is theoretically analyzed and numerically simulated. The quantum mechanical calculations of the equilibrium geometry and the energies and intensities of the lowest singlet electronic transitions in pseudoisocyanine chloride and its linear (chain) oligomers are fulfilled. The data of these calculations can serve as parameters of the analyzed model of interaction of J aggregates with radiation in the oneparticle density matrix approximation. This model takes into account relaxation processes, the annihilation of excitations at neighboring molecules, and inho mogeneous broadening. Assuming that the inhomogeneous broadening is absent, calculations demonstrate the existence of spatial bistability, molecular switching waves, and dissipative solitons. The effect of the inhomogeneous broadening and the radiation intensity on the effective coherence length in linear (chain) J aggregates is analyzed