Publications by authors named "Sergey V Firstov"

The first bismuth-doped superfluorescent fiber source (SFS) operating at 1.44 μm was developed. An SFS maximum output power in the double-pass backward configuration reached 82 mW with a fairly high efficiency of 31% at a pump wavelength of 1310 nm.

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Luminescence emission and excitation spectra of bismuth-doped silica optical fibers free of other dopants have been obtained to construct an emission-excitation map in a wide wavelength range of 400-1600 nm. The main low-lying energy levels of the bismuth active centers in such fibers have been determined. For the first time (to our knowledge), optical gain and lasing have been obtained in such fibers.

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IR luminescence and optical gain in a Pb-doped fiber have been observed for the first time. Absorption, luminescence and pump on/pump off optical gain spectra, as well as luminescence decay time, have been measured in these fibers. Comparison of optical active center characteristics in Pb-doped and Bi-doped fibers of the same composition indicates an essential difference of optical active centers in these two types of fibers.

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Bismuth-doped fiber lasers operating in the range 1300-1470 nm have been demonstrated for the first time, to our knowledge. It has been shown that Bi-doped alumina-free phosphogermanosilicate fibers reveal optical gain in a wavelength range of 1240-1485 nm with pumping at 1205, 1230, or 808 nm.

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Plasma chemical technology is experimentally applied to the fabrication of a Bi-activated alumosilicate-core pure-silica-cladding fiber preform. To the best of our knowledge, this is the first time this technology has been applied in this way. We measure gain efficiency at pumping by a 1058 nm wavelength Yb fiber laser in a piece of a newly obtained fiber 20 m in length within 100-1200 nm wavelengths band.

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