Responsive Spiral Photonic Structures for Visible Vapor Sensing, Pattern Transformation and Encryption

Two photon polymerisation using direct laser writing is a burgeoning field of research, with recent focus being placed on bringing added value to microstructures, by incorporating soft, responsive polymers. Moving the micron-scale can have profound impact such stimuli-responsive materials, whose speed actuation be increased many-fold compared their mm-scale counterparts. Here, fabrication submicron 2D photonic structures, based vapor-responsive photoresist refractive index <1.55, in visible wavelength range. The fabricated concentric spiral arrays are evaluated for feasibility as vapor sensors testing spectral and structural color reproducibility reversibility under water, ethanol, isopropanol, acetone vapors. This approach allows realization predictable uniform displays that modulated upon stimuli response. transmitted colour dry hydrated states accurately modelled. knowledge used design demonstrate structures cloaking image transformation. Such capability encryption anti-counterfeiting applications.