Three-Dimensional Manipulation of an Azo Polymer Liquid Crystal with Unpolarized Light

Manipulation of azobenzene moieties in polymer liquid crystals (PLCs) in three dimensions by means of unpolarized light is demonstrated here. When cis-azobenzenes, produced by irradiation for 1 min with unpolarized light at 366 nm, were subsequently irradiated at 436 nm, the resulting trans-azobenzenes could be aligned in any direction, according to the direction of propagation of the irradiating light, it was found. Transmittance measurements, UV absorption spectra, and conoscopic observations (see cover) are reported. Azobenzene-containing PLCs have potential applications in optical data storage.