Photoinduced three-dimensional structures in amorphous and LC polymers

The 3D anisotropy generated by photoorientation of thin films of azobenzene containing polymers can be determined using waveguide spectroscopy [1-4]. Irradiation of the films in the glassy state of the polymers with polarized light resulted in almost perfectly oblate index ellipsoids. Recently [5], we have found, that in the case of LC polymers the anisotropy can be amplified by annealing. The investigation of a number of polymers shows, that various types of 3D orientations (biaxial and uniaxial, oblate and homeotropic) can be obtained by such a annealing procedure. The film interfaces seem to play a crucial role for the respective behaviour.