Ultra-Broadband Directional Infrared Radiation in the Atmospheric Window (UMD)

Abstract

In this basic research program we propose to analyze, numerically evaluate through simulations, and perform proof-of-principle experiments to understand the nonlinear processes responsible for the generation of ultra-broadband radiation. The fully 3D wave equation for the electric field together with the linear and nonlinear polarization fields will be derived and numerical simulations performed. Because of the highly nonlinear nature of these interactions and the resulting generation of broadband radiation it will be necessary to extend the conventional slowly varying wave amplitude approximation model to more accurately describe the generation of a super continuum output spectrum.A proof-of-principle experiment will be designed and set up using a high power CO2 Laser. The CO2 laser will be configured to operate with multiple, closely spaced spectral lines using wavelength selection optics in the laser cavity. The beat wave created by these laser lines in a nonlinear crystal such as GaAs will be experimentally studied for the generation of side bands and the broadening of the overall spectrum. Different spectral regions within the CO2 gain spectrum will be investigated for dispersion effects on the spectral and temporal profiles of the output laser pulse. Experimental results will be compared and benchmarked with theory and simulation results. Research results will be published in refereed journals and presented at organized conferences and reviews.Experiments will take place at the University of Maryland using a wide range of laser facilities, including a MW peak power CO2 laser, and diagnostics for measuring the spectral broadening and spectral power distribution in the LW-IR and MW-IR regions. In the simulations, the laser propagation and matter interaction code BTUL (Bidirectional, 3D, UltrabroadbandLaser) developed at the University of Maryland will be used to model and evaluate these processes. The BTUL code is unique in that it can simulate extreme spectral broadening and handle bi-directional wave propagation.

Document Details

Document Type
DoD Grant Award
Publication Date
May 08, 2020
Source ID
N000142012285

Entities

People

  • Antonio Ting

Organizations

  • Office of Naval Research
  • United States Navy
  • University of Maryland

Tags

Fields of Study

  • Physics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Computational Fluid Dynamics (CFD)
  • Optical Physics and Photonics.

Technology Areas

  • Directed Energy
  • Space