Transient Magnesium-Based Color Pixels

Optical devices applied in research and industry environments utilize wavelength filtering to achieve optical responses necessary for proper function. Most optical signal filters require power during usage and/or modification, and so the development of a power-free reconfigurable photonic alternative is desired. We realize Mg-based nanophotonic color pixels with transient functionality which filter visible light based on nanocavity interference. These transient color pixels can be fabricated to transmit any hue within the sRGB gamut. We determine the transient optical response of the Mg-based pixels during their dissolution in water under pH neutral, room temperature conditions. Color is completely negated in under 10 minutes, making these pixels useful for encryption and anti-counterfeiting. Our spectroscopic ellipsometry experiments are corroborated by 3D full-field computation using finite-difference time-domain (FDTD) simulations. The application of Mg as a material for transient photonic devices allows for the rapid, inexpensive adjustment of optical responses for wavelength filtering.