Length-scale dependence of surface relief gratings in azobenzene side-chain polymers

Polarized irradiation of azobenzene side-chain polymers yields intriguing s urface relief structures. Up to now, the physical mechanism of this process is unclear. We report on a study aimed at clarifying the intrinsic length scales of the substantial mass transport which evolves during laser irradia tion. We vary the period of an incident intensity grating by more than an o rder of magnitude, and investigate the resulting relief amplitudes with ato mic force microscopy. (C) 2001 Elsevier Science B.V. All rights reserved.