Research of optical fiber’s hermetic carbon coatings used in harsh conditions
DOI: 10.22184/1993-7296.FRos.2019.13.5.476.484
Hermetic Carbon Coatings Used
in Harsh Conditions
V. B. Romashova1,3, D. S. Shaimadiyeva1,2, N. V. Burov1
JSC «Leningrad Laser Systems», St. Petersburg
St. Petersburg National Research University of Information Technologies, Mechanics and Optics, St. Petersburg
Saint Petersburg State University of Aerospace Instrumentation, St. Petersburg
Hermetic carbon coatings of various thicknesses in the range from 1 to 100 nm for optical fibers are characterized by confocal Raman spectroscopy and atomic force microscopy. In the course of the research, standard Raman far-field spectra were obtained in the region from 1000 to 2000 cm−1 using 5 individual components: different types of graphite-like and disordered phases. A new spectroscopic indicator is also proposed, which provides a measure of the soot fraction in carbon materials. Studies using the TERS (tip-enhanced Raman scattering) method confirmed the complex structure of the Raman D band of the first order assigned to disordered vibrations of the graphite lattice. In addition, using this method, it was proved that carbon allotropes are formed in protective coatings, such as carbon nanotubes.
Keywords: optical fibre testing, protective coatings, carbon allotropes, Raman spectroscopy, TERS.
Received:30.07.2019. Accepted: 20.08.2019.