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Title: Infrared dielectric function of polydimethylsiloxane and selective emission behavior

Abstract

The complex refractive index of polydimethylsiloxane (PDMS) is determined in the wavelength range between 2.5 μm and 16.7 μm. The parameters of a Drude-Lorentz oscillator model (with 15 oscillators) are extracted from Fourier transform infrared spectroscopy reflectance measurements made on both bulk PDMS and thin films of PDMS deposited on the gold coated silicon substrates. It is shown that thin films of PDMS atop gold exhibit selective emission in the 8 μm to 13 μm atmospheric transmittance window, which demonstrates that PDMS, especially due to its ease of deposition, may be a viable material for passive radiative cooling applications.

Authors:
; ;  [1];  [2]
  1. Department of Mechanical Engineering, Columbia University, New York, New York 10027 (United States)
  2. Skycatch, San Francisco, California 94107 (United States)
Publication Date:
OSTI Identifier:
22594345
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; DEPOSITION; DEPOSITS; DIELECTRIC MATERIALS; EMISSION; FOURIER TRANSFORM SPECTROMETERS; FOURIER TRANSFORMATION; GOLD; OSCILLATORS; RADIATIVE COOLING; REFRACTIVE INDEX; SILICON; SILOXANES; SUBSTRATES; THIN FILMS; WAVELENGTHS

Citation Formats

Srinivasan, Arvind, Czapla, Braden, Narayanaswamy, Arvind, E-mail: arvind.narayanaswamy@columbia.edu, and Mayo, Jeff. Infrared dielectric function of polydimethylsiloxane and selective emission behavior. United States: N. p., 2016. Web. doi:10.1063/1.4961051.
Srinivasan, Arvind, Czapla, Braden, Narayanaswamy, Arvind, E-mail: arvind.narayanaswamy@columbia.edu, & Mayo, Jeff. Infrared dielectric function of polydimethylsiloxane and selective emission behavior. United States. doi:10.1063/1.4961051.
Srinivasan, Arvind, Czapla, Braden, Narayanaswamy, Arvind, E-mail: arvind.narayanaswamy@columbia.edu, and Mayo, Jeff. 2016. "Infrared dielectric function of polydimethylsiloxane and selective emission behavior". United States. doi:10.1063/1.4961051.
@article{osti_22594345,
title = {Infrared dielectric function of polydimethylsiloxane and selective emission behavior},
author = {Srinivasan, Arvind and Czapla, Braden and Narayanaswamy, Arvind, E-mail: arvind.narayanaswamy@columbia.edu and Mayo, Jeff},
abstractNote = {The complex refractive index of polydimethylsiloxane (PDMS) is determined in the wavelength range between 2.5 μm and 16.7 μm. The parameters of a Drude-Lorentz oscillator model (with 15 oscillators) are extracted from Fourier transform infrared spectroscopy reflectance measurements made on both bulk PDMS and thin films of PDMS deposited on the gold coated silicon substrates. It is shown that thin films of PDMS atop gold exhibit selective emission in the 8 μm to 13 μm atmospheric transmittance window, which demonstrates that PDMS, especially due to its ease of deposition, may be a viable material for passive radiative cooling applications.},
doi = {10.1063/1.4961051},
journal = {Applied Physics Letters},
number = 6,
volume = 109,
place = {United States},
year = 2016,
month = 8
}
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