English

Kinetics of photoinduced ordering in azo-dye films: two-state and diffusion models

Materials Science 2009-08-27 v1 Statistical Mechanics

Abstract

We study the kinetics of photoinduced ordering in the azo-dye SD1 photoaligning layers and present the results of modeling performed using two different phenomenological approaches. A phenomenological two state model is deduced from the master equation for an ensemble of two-level molecular systems. Using an alternative approach, we formulate the two-dimensional (2D) diffusion model as the free energy Fokker-Planck equation simplified for the limiting regime of purely in-plane reorientation. The models are employed to interpret the irradiation time dependence of the absorption order parameters extracted from the available experimental data by using the exact solution to the light transmission problem for a biaxially anisotropic absorbing layer. The transient photoinduced structures are found to be biaxially anisotropic whereas the photosteady and the initial states are uniaxial.

Keywords

Cite

@article{arxiv.0812.1925,
  title  = {Kinetics of photoinduced ordering in azo-dye films: two-state and diffusion models},
  author = {Alexei D. Kiselev and Vladimir G. Chigrinov and Hoi-Sing Kwok},
  journal= {arXiv preprint arXiv:0812.1925},
  year   = {2009}
}

Comments

revtex4, 34 pages, 9 figures

R2 v1 2026-06-21T11:50:19.952Z