Direct method of extracting broadband complex refractive index from spectrophotometric measurements: an application to polydimethylsiloxane for passive radiative cooling.
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引用次数: 0
Abstract
We describe an algorithm to extract the complex refractive index of a material from broadband reflectance and transmittance measurements taken by spectrophotometers. The algorithm combines Kramers-Kronig analysis with an inversion of Fresnel's equations to provide a direct method of solving for the refractive index which is accurate, even for weakly absorbing materials, and easily applicable to radiative heat transfer calculations. The algorithm is validated by extracting the complex refractive index of polydimethylsiloxane between 0.25 μm and 100 μm and comparing against existing literature. We also discuss the importance of broadband optical properties to passive radiative cooling and details of the uncertainty analysis of the algorithm.
期刊介绍:
Accounts of Chemical Research presents short, concise and critical articles offering easy-to-read overviews of basic research and applications in all areas of chemistry and biochemistry. These short reviews focus on research from the author’s own laboratory and are designed to teach the reader about a research project. In addition, Accounts of Chemical Research publishes commentaries that give an informed opinion on a current research problem. Special Issues online are devoted to a single topic of unusual activity and significance.
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