Mid-infrared epsilon-near-zero modes in ultra-thin phononic films
Abstract
We demonstrate strong, narrow-band selective absorption and subsequent selective thermal emission from ultra-thin planar films of polar materials at mid-infrared wavelengths. Our structures consist of AlN layers of varying thicknesses deposited upon molybdenum ground planes. We demonstrate coupling to the Berreman mode at frequencies at, or near, the longitudinal optical phonon energy of AlN. Samples are characterized experimentally by temperature-, angle-, and polarization-dependent Fourier transform infrared reflection and emission spectroscopy and modeled using a transfer matrix method approach. Strong, spectrally selective thermal emission, with near angle-independent spectral position, is demonstrated from an AlN layer with thickness t<λo/100.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 28, 2017
- Source ID
- 10.1063/1.4996213
Entities
People
- Anthony J. Hoffman
- C. M. Roberts
- D. Wasserman
- K. Feng
- Leland Nordin
- O. Dominguez
- V. A. Podolskiy
- W. Streyer
- Zhaoyuan Fang
Organizations
- Army Research Office
- National Science Foundation
- University of Massachusetts Lowell
- University of Notre Dame
- University of Texas at Austin