Research Area 9 Materials Science: Anistropic Microstructurally-engineered Polycrystals for increased Laser Engergy (AMPLE)
Abstract
The objective of the proposed effort is to develop and fabricate, through microstructure engineering, novel laser gain ceramics with a unique combination of high thermal conductivity and optical clarity. The proposed effort is based on a new opportunity to fabricate laser gain ceramics with dramatically improved thermal conductivity relative to typical cubic oxides to establish a new paradigm for diode pumped solid state lasers. The enhanced thermal conductivity is achieved primarily through the design and fabrication of highly anisotropic grains, with nanometer dimensions along the two optical axes (to minimize photon scattering) and micrometer dimensions in the cooling direction (preserving high thermal conductivity). The proposed research effort integrates modeling and experimental efforts in chemistry, materials processing, materials characterization, thermal transport, and laser engineering to fully address the stated technical objective. The proposed work is organized around five primary research goals: 1) to synthesize high purity Al2O3 and AlN powders, including nanocrystalline Al2O3 and AlN, high aspect ratio Al2O3 and AlN, and high aspect Al2O3 + RE and AlN + RE powder; 2) to produce quality laser gain ceramics with isotropic and anisotropic micro/nano-structure tuned for high optical and thermal properties using a non-equilibrium powder densification called current activated pressure assisted densification (CAPAD); 3) to characterize the micro/nano-structure ceramics, measure the optical properties (absorption and fluorescence spectra, fluorescence mapping), and formulate photon transmission models to help interpret and optimize optical properties; 4) to determine the thermo-mechanical properties of the ceramic gain media and use phonon models(Monte-Carlo ray tracing) to interpret results; and 5) to characterize optimized anisotropic microstructurally-engineered polycrystalline ceramics in diode pumped laser cavities.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 06, 2017
- Source ID
- W911NF1610571
Entities
People
- Javier E Garay
Organizations
- Army Contracting Command
- United States Air Force
- University of California, San Diego