Optical alignment and patterning of nanoscale microdomains in a block copolymer thin film

Optical 3D alignment of nanocylinders has been successfully attained for thin films of a block copolymer (see figure) comprising azobenzene-containing liquid-crystalline polymers and poly(ethylene oxide) via photoinduced massive migration. ne out-of-plane and inplane alignments are achieved by controlling the film thickness and selection of linear polarization direction upon illumination, respectively.