Publications by authors named "L V Kotov"

Femtosecond (fs) time-resolved magneto-optics is applied to investigate laser-excited ultrafast dynamics of one-dimensional nickel gratings on fused silica and silicon substrates for a wide range of periodicities Λ = 400-1500 nm. Multiple surface acoustic modes with frequencies up to a few tens of GHz are generated. Nanoscale acoustic wavelengths Λ/ have been identified as -spatial harmonics of Rayleigh surface acoustic wave (SAW) and surface skimming longitudinal wave (SSLW), with acoustic frequencies and lifetimes being in agreement with theoretical calculations.

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In this paper, we present a novel single-mode Yb-doped fiber with 14 µm core and 45 µm cladding diameter. A 976 nm all-fiber high-power amplifier was manufactured based on this fiber. 10-mm-long fiber taper was used to launch the pump light, and guidance of the high NA pump was provided by a glass-air interface.

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For the first time, to the best of our knowledge, we present an all-fiber polarization-maintaining passively mode-locked picosecond laser operated at 980 nm. The laser cavity had a ring configuration with a semiconductor saturable absorber mirror as a mode-locking element. As an active medium, we used a specially designed cladding-pumped Yb-doped fiber with reduced cladding-to-core diameter ratio.

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Transverse-electric (TE) surface plasmons (SPs) are very unusual for plasmonics phenomenon. Graphene proposes a unique possibility to observe these plasmons. Due to transverse motion of carriers, TE SPs speed is usually close to bulk light one.

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We report, for the first time to our knowledge, on a single-mode millijoule-level 100-nanosecond Er-doped fiber laser operating near 1550 nm. The system features a newly developed 35-μm-core Yb-free double-clad Er-doped fiber based on P(2)O(5)-Al(2)O(3)-SiO(2) glass matrix and produces pulses with energy as high as 1 mJ at repetition rates of 1-10 kHz.

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