title: Multilayer mirrored bubbles with spatially-chirped and elastically-tuneable optical bandgaps.
abstract: We demonstrate the multifolding Origami manufacture of elastically-deformable Distributed Bragg Reflector (DBR) membranes that reversibly color-tune across the full visible spectrum without compromising their peak reflectance. Multilayer films composed of alternating transparent rubbers are fixed over a 300 μm wide pinhole and deformed by pressure into a concave shape. Pressure-induced color tuning from the near-IR to the blue arises from both changes in thickness of the constituent layers and from tilting of the curved DBR surfaces. The layer thickness and color distribution upon deformation, the band-gap variation and the repeatability of cyclic color tuning, are mapped through micro-spectroscopy. Such spatially-dependent thinning of the film under elastic deformation produces spatial chirps in the color, and are shown to allow reconstruction of complex 3D strain distributions.
authors.affiliation: Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK.
authors.forename: Gen
authors.initials: G
authors.lastname: Kamita
authors.forename: Mathias
authors.initials: M
authors.lastname: Kolle
authors.forename: Fumin
authors.initials: F
authors.lastname: Huang
authors.forename: Jeremy J
authors.initials: JJ
authors.lastname: Baumberg
authors.forename: Ullrich
authors.initials: U
authors.lastname: Steiner
mesh_terms: D003116:Color; D003124:Colorimetry / Q000295:instrumentation*; D017076:Computer-Aided Design; D055119:Elastic Modulus; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007909:Lenses; D008567:Membranes, Artificial; D045423:Microbubbles; D012031:Refractometry / Q000295:instrumentation*; D013314:Stress, Mechanical
chemical_list: D008567:Membranes, Artificial