标题： 使用多次散射的蒙特卡罗模拟设计角度无关的结构颜色 显示英文标题

标题： Designing angle-independent structural colors using Monte Carlo simulations of multiple scattering

摘要： 无序纳米结构在可见光波长尺度上具有相关性，可以表现出与角度无关的结构色。 这些材料可以在某些应用中替代染料，因为颜色可调且耐光漂白。 然而，设计具有预定颜色的纳米结构很困难，尤其是在应用（例如化妆品或显示器）需要特定组成材料时。 解决这一约束设计问题的一种通用方法是建模和优化：使用能够预测给定系统颜色的模型，在约束条件下优化模型参数以实现目标颜色。 为了使这种方法有效，模型必须做出准确的预测，这具有挑战性，因为无序纳米结构存在多重散射。 为了解决这个挑战，我们开发了一种蒙特卡洛模型，用于模拟球形颗粒或空洞无序排列中的光多重散射。 当考虑薄膜表面的粗糙度、粒子多分散性和组件的波长依赖性吸收时，该模型与测量结果有定量一致性。 与离散数值模拟不同，我们的模型是根据实验变量进行参数化的，简化了模拟与制造之间的联系。 为了展示这种方法，我们在实验系统中再现了雄性山蓝鸲（Sialia currucoides）的颜色，使用了规定的成分和一种易于制造的微结构。 最后，我们使用该模型找到了给定系统下与角度无关的结构色的极限。 这些结果使得在许多不同应用中能够采用工程设计方法来实现结构色。 显示英文摘要

摘要： Disordered nanostructures with correlations on the scale of visible wavelengths can show angle-independent structural colors. These materials could replace dyes in some applications because the color is tunable and resists photobleaching. However, designing nanostructures with a prescribed color is difficult, especially when the application -- cosmetics or displays, for example -- requires specific component materials. A general approach to solving this constrained design problem is modeling and optimization: using a model that predicts the color of a given system, one optimizes the model parameters under constraints to achieve a target color. For this approach to work, the model must make accurate predictions, which is challenging because disordered nanostructures have multiple scattering. To address this challenge, we develop a Monte Carlo model that simulates multiple scattering of light in disordered arrangements of spherical particles or voids. The model produces quantitative agreement with measurements when we account for roughness on the surface of the film, particle polydispersity, and wavelength-dependent absorption in the components. Unlike discrete numerical simulations, our model is parameterized in terms of experimental variables, simplifying the connection between simulation and fabrication. To demonstrate this approach, we reproduce the color of the male mountain bluebird (Sialia currucoides) in an experimental system, using prescribed components and a microstructure that is easy to fabricate. Finally, we use the model to find the limits of angle-independent structural colors for a given system. These results enable an engineering design approach to structural color for many different applications.