STP759: 1.3 μm Laser Rate Calorimetry and Photoacoustic Studies of the Surface and Bulk Optical Absorption in CaF2 Single Crystal Samples

    Fernelius, NC
    University of Dayton Research Institute, Dayton, Ohio

    Dempsey, DV
    University of Dayton Research Institute, Dayton, Ohio

    O'Quinn, DB
    University of Dayton Research Institute, Dayton, Ohio

    Pages: 17    Published: Oct 1981


    There are a variety of techniques for measuring the surface-to-bulk optical absorption ratio most of which require specially prepared samples. In most works only one technique was employed on a given sample. In this work we tried three different techniques to measure the surface-to-bulk optical absorption ratio, r, at 1.3 μm on a group of similar CaF2 single crystal samples. Laser rate calorimetry results on a series of samples of varying thickness gave r = βSB = 0.14 cm where βS is the surface absorption and βB is the bulk optical absorption in cm−1. A second slope was not seen on the long bar samples which implies that r is less than 0.3 cm. Analysis of photoacoustic chopping frequency variation studies using the Bennett-Forman theory gave r = 0.07 cm about half the multithickness result. Considering the experimental uncertainties all three technique yielded consistent results.


    CaF, 2, laser calorimetry, laser windows, optoacoustic, photoacoustic, surface-to-bulk optical absorption

    Paper ID: STP36997S

    Committee/Subcommittee: F01.02

    DOI: 10.1520/STP36997S

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