Determining the Out-of-Plane Thermal Expansion Coefficient by Analyzing the Temperature Dependence of Thin-Film Interference Fringes

Abstract

We analyze a new method for determining the out-of-plane coefficient of thermal expansion for thin films of transparent materials. The method is based on the measurement of interference peaks recorded in transmission spectra as a function of sample temperature. The locations of interference peaks depend on the optical path. We show how a consideration of Lorentz-Lorenz equation, in addition to the transmission peak equation, can separate the different contributions of index and physical pathlength to the optical path. The analysis is generalized to include the effects of uniaxial material properties (such as anisotropic linear thermal expansion and birefringence). By applying this method of analysis to recent data, we demonstrate the importance of including the effect of the thermo-optic coefficient in interpreting observed data

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Document Details

Document Type
Technical Report
Publication Date
Feb 25, 2019
Accession Number
AD1096652

Entities

People

  • A. Rosenberg
  • G. Beadie
  • James S. Shirk

Organizations

  • United States Naval Research Laboratory

Tags

Communities of Interest

  • Advanced Electronics
  • Engineered Resilient Systems

DTIC Thesaurus Topics

  • Birefringence
  • Climate Change
  • Films
  • Low Temperature
  • Materials
  • Materials Laboratories
  • Measurement
  • Mechanical Properties
  • Optical Materials
  • Optics
  • Physical Properties
  • Polymers
  • Refractive Index
  • Thermal Expansion
  • Thick Films
  • Thickness
  • Thin Films

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Optical Physics and Photonics.
  • Spectroscopy.