Cryogenic measurement of the optical absorption coefficient in sapphire crystals at 1.064 μm for the Large-scale Cryogenic Gravitational wave Telescope
نویسندگان
چکیده
We have applied laser calorimetry to the measurement of optical absorption in monocrystalline sapphire at cryogenic temperatures. Sapphire is a promising candidate for the mirror substrates of the Large-scale Cryogenic Gravitational wave Telescope. The optical absorption coefficients of different sapphire samples at a wavelength of 1.064 μm at 5K were found to average 90 ppm/cm.
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