Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA, 02155, USA.
Silklab, Tufts University, 200 Boston Avenue, Medford, MA, 02155, USA.
Adv Mater. 2019 Feb;31(5):e1805312. doi: 10.1002/adma.201805312. Epub 2018 Dec 6.
Naturally occurring iridescent systems produce brilliant color displays through multiscale, hierarchical assembly of structures that combine reflective, diffractive, diffusive, or absorbing domains. The fabrication of biopolymer-based, hierarchical 3D photonic crystals through the use of a topographical templating strategy that allows combined optical effects derived from the interplay of predesigned 2D and 3D geometries is reported here. This biomaterials-based approach generates 2D diffractive optics composed of 3D nanophotonic lattices that allow simultaneous control over the reflection (through the 3D photonic bandgap) and the transmission (through 2D diffractive structuring) of light with the additional utility of being constituted by a biocompatible, implantable, edible commodity textile material. The use of biopolymers allows additional degrees of freedom in photonic bandgap design through directed protein conformation modulation. Demonstrator structures are presented to illustrate the lattice multifunctionality, including tunable diffractive properties, increased angle of view of photonic crystals, color-mixing, and sensing applications.
天然彩虹色系统通过多级、分层的结构组装，将反射、衍射、扩散或吸收区域结合在一起，从而产生鲜艳的颜色显示。本文报道了一种通过形貌模板策略制造基于生物聚合物的分层 3D 光子晶体的方法，该策略允许结合源自二维和三维几何形状相互作用的光学效果。这种基于生物材料的方法生成了由 3D 纳米光子晶格组成的二维衍射光学元件，可同时控制光的反射（通过 3D 光子带隙）和传输（通过二维衍射结构），并且具有由生物相容性、可植入、可食用商品纺织材料构成的额外优点。生物聚合物的使用通过定向蛋白质构象调制为光子带隙设计提供了更多自由度。展示了一些演示结构，说明了晶格的多功能性，包括可调谐的衍射特性、增加光子晶体的视角、颜色混合和传感应用。
