Generic stochastic Monte Carlo model of the photoinduced mass transport in azo-polymers and fine structure of Surface Relief Gratings

¹ Institute of Physics, Wroclaw University of Technology - Wroclaw, Poland
² Institute of Physical and Theoretical Chemistry, Wroclaw University of Technology - Wroclaw, Poland

Received: 4 October 2013
Accepted: 10 January 2014

Abstract

We study theoretically the possible origin of a double-peak fine structure of Surface Relief Gratings in azo-functionalized poly(etherimide) reported recently in experiments. To improve the statistics of experimental data additional measurements were done. For the theoretical analysis we develop a stochastic Monte Carlo model for photoinduced mass transport in azobenzene-functionalized polymer matrix. The long sought-after transport of polymer chains from bright to dark places of the illumination pattern is demonstrated and characterized, various scenarios for the intertwined processes of build-up of density and SRG gratings are examined. Model predicts that for some azo-functionalized materials double-peak SRG maxima can develop in the permanent, quasi-permanent or transient regimes. Available experimental data are interpreted in terms of model's predictions.