Accession Number : AD1009895


Title :   Novel Optical Fiber Materials With Engineered Brillouin Gain Coefficients SSL 1: Novel Fiber Lasers


Descriptive Note : Technical Report,01 Oct 2012,30 Sep 2015


Corporate Author : University of Illinois - Urbana Champaign United States


Personal Author(s) : Dragic,Peter D ; Ballato,John


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/1009895.pdf


Report Date : 29 Dec 2015


Pagination or Media Count : 56


Abstract : This 2-year program (with 1 year no-cost extension) sought to investigate novel optical materials suitable for use in high-power narrow-linewidth fiber lasers. A complete model for the mass density, acoustic velocity, acoustic attenuation, photoelastic (Pockels) coefficients, and refractive index has been developed for multi-component glasses. It has been utilized to characterize several materials (data are provided herein), including Group I and II oxides, MgAl2O4 (spinel), alumina, LuAG (a garnet), and several rare earths (RE2O3), including determination of compositions that give rise to near-zero Brillouin gain. Fibers were produced from these precursors (crystal and glass phase), clad in silica, utilizing the molten core processing technique. Measurement test beds have been developed to determine the key acoustic and photoelastic constants of these fibers, in order to validate the model. Within the scope of this work, suppression of Brillouin scattering by 10dB relative to conventional fiber has been routine. Furthermore, we have investigated some rare-earth-doped versions of these fibers, and other novel materials have been identified as promising and these were continued to be studied during the extension period. We point out that this limited report represents only highlights from the numerous findings accumulated during this program. They can be found in greater detail in the roughly 175 printed pages in the resulting 17 journal publications (quite a bit more if one includes a number of archival conference proceedings).


Descriptors :   optical materials , brillouin scattering , High energy lasers , glass , acoustic properties , raman scattering


Distribution Statement : APPROVED FOR PUBLIC RELEASE