Exploiting Light Interferences to Generate Micrometer‐High Superstructures from Monomeric Azo Materials with Extensive Orientational Mobility

Photochromic azo materials have stirred considerable interest for their ability to mechanically respond polarized light through large photoinduced migration and orientation processes. In order apprehend the microscopic dynamics behind extensive mass transport occurring under interferential illumination, two compounds differing by propensity form hydrogen bonds are synthesized processed as nondoped glassy thin films. Interferential irradiation using polarization intensity patterns reveals fully distinct responses. Regular nanometer-high surface relief gratings transform into micrometer superstructures with an amplitude ten times higher than initial film thickness when latter polarization. Systematic comparisons between in terms of thermal properties, photochromism solution solid state, photomigration carried out. The progressive formation is ascribed successive first one relates fast due impinging structured light, second promoted slower thermally activated zig-zag-like diffusion Z-E relaxation, which turn requests high orientational mobility causes nanomechanical changes. Such studies should provide novel structural guidelines material fluidity rapidly achieve highly rewritable at low irradiance.