Browsing by Author "Pavlyuk, A. A."

Now showing items 1-12 of 12

    • All-space existence and dispersion of athermal directions in monoclinic KY(WO4)2 

      Filippov, V.; Yumashev, K. V.; Kuleshov, N. V.; Pavlyuk, A. A.; Loiko, P. A. (Elsevier, 2014)
      The analytical expressions for thermo-optic coefficients, dn/dT, for “fast” and “slow” light waves propagating along the arbitrary direction in a biaxial crystal are derived. On the basis of these expressions, the all-space analysis of existence of athermal directions is performed for monoclinic and biaxial KY(WO4)2 at 1.03 μm. The calculations are performed for an arbitrary light ...
      2016-02-08

    • Anisotropy of the photo-elastic effect in Nd : KGd(WO4) 2 laser crystals 

      Loiko, P. A.; Savitski, V. G.; Kemp, A.; Pavlyuk, A. A.; Kuleshov, N. V.; Yumashev, K. V. (Wiley, 2014)
      The anisotropy of thermal lensing and the photo-elastic effect is characterized for diodepumped Nd : KGd(WO4)2 crystals cut along the Np and Ng optical indicatrix axes and along its optical axis, O = Ng + 43°, at a laser wavelength of 1067 nm. Distortions in the spatial profile of the output laser beam are analyzed. The thermal lens is astigmatic; the orientation of its principal ...
      2016-02-08

    • CW and Q-switched diode-pumped laser operation of Yb 3+:NaLa(MoO4)2 

      Mandrik, A. V.; Troshin, A. E.; Kisel, V. E.; Yasukevich, A. S.; Klavsut, G. N.; Kuleshov, N. V.; Pavlyuk, A. A. (Springer, 2005)
      Continuous wave (CW) and Q-switched diode-pumped laser operation of Yb3+:NaLa(MoO4)2 single crystal was to our knowledge, demonstrated for the first time. A CW output power of 220 mW and slope efficiency of 46% were obtained. Q-switched laser operation was achieved with a pulse duration of 60 ns average output power of 70mW and slope efficiency of 22%.
      2016-03-24

    • Energy transfer in Tm,Ho:KYW crystal and diode-pumped microchip laser operation 

      Kurilchik, S. V.; Gusakova, N. V.; Demesh, M. P.; Yasukevich, A. S.; Kisel, V. E.; Pavlyuk, A. A.; Kuleshov, N. V. (Optical Society of America, 2016)
      An investigation of Tm-Ho energy transfer in Tm(5at.%), Ho(0.4at.%):KYW single crystal by two independent techiques was performed. Based on fluorescence dynamics measurements, energy transfer parameters P71 and P28 for direct (Tm→Ho) and back (Ho→Tm) transfers, respectively, as well as equilibrium constant Θ were evaluated. The obtained results were supported by calculation of ...
      2016-05-12

    • Erratum to: Thermo‑optic coefficients of Nd‑doped anisotropic KGd(WO4)2, YVO4 and GdVO4 laser crystals 

      Loiko, P. A.; Yumashev, K. V.; Kuleshov, N. V.; Pavlyuk, A. A. (2016)
      Erratum to: Thermo‑optic coefficients of Nd‑doped anisotropic KGd(WO4)2, YVO4 and GdVO4 laser crystals / P. A. Loiko [et al.] // Applied Physics B. – 2016. – Vol. 129.
      2017-11-22

    • High efficient 12W diode-pumped actively Q-switched YB:KGD(WO4)2 laser 

      Kisel, V. E.; Rudenkov, А. S.; Kuleshov, N. V.; Pavlyuk, A. A. (BNTU, 2013)
      Compact diode-pumped actively Q-switched Yb:KGW laser is demonstrated with optical-to-optical efficiency of 50%. In a Z-shaped laser cavity configuration output power of 12.2 W with repetition rate up to 50 kHz and pulse duration of 10-24 ns was obtained. The maximum pulse peak power of 70 kW was achieved. The laser output beam profile was Gaussian up to maximum pump powers with ...
      2018-05-28

    • In-Band Pumped Continuous-Wave Lasers Based on Ho:KY(WO4)2 Crystal and Ho:KGdYbY(WO4)2 Epitaxial Layer 

      Dernovich, O. P.; Gusakova, N. V.; Kisel, V. E.; Kravtsov, A. V.; Guretsky, S. A.; Pavlyuk, A. A.; Kuleshov, N. V. (БНТУ, 2020)
      2 μm lasers are in demand for a number of practical applications, such as environmental monitoring, remote sensing, medicine, material processing, and are also used as a pump sources for optical parametric generators. Crystals of double potassium tungstates doped with ions of rare-earth elements were shown to be promising materials both for the creation of classical solid-state ...
      2020-12-18

    • In-band pumped room-temperature Er:KY(WO4)2 laser emitting around 1:6 mm 

      Gorbachenya, K. N.; Kisel, V. E.; Yasukevich, A. S.; Pavlyuk, A. A.; Kuleshov, N. V. (Maik Nauka-Interperiodica Publishing, 2013)
      We present efficient continuous-wave operation of an Er:KY(WO 4)2 crystal under in-band pumping by a compact diode-pumped Er, Yb:GdAl3(BO3)4 laser. Maximum slope efficiency of 27% and output power of 35 mW at 1609.5 nm were obtained with beam propagation factor M2 < 1:2. Absorption and stimulated emission cross-section spectra, as well as the radiative lifetime of the 4I13=2 ...
      2016-05-12

    • Spectroscopic and photoluminescence characterization of Eu 3+-doped monoclinic KY(WO4)2 crystal 

      Loiko, P. A.; Dashkevich, V. I.; Bagaev, S. N.; Orlovich, V. A.; Yasukevich, A. S.; Yumashev, K. V.; Kuleshov, N. V.; Dunina, E. B.; Kornienko, A. A.; Vatnik, S. M.; Pavlyuk, A. A. (Elsevier, 2014)
      Monoclinic 2 at% Eu-doped KY(WO4)2 is grown by top-seeded solution growth method. Polarizationresolved absorption and stimulated-emission cross-section spectra are determined for this crystal. Spectroscopic properties of Eu:KY(WO4)2 are modeled within conventional Judd–Ofelt theory, as well as theory of f–f transition intensities for systems with anomalously strong configuration ...
      2016-02-08

    • Spectroscopy of tetragonal Eu:NaGd(WO4)2 crystal 

      Loiko, P. A.; Vilejshikova, E. V.; Mateos, X.; Serres, J. M.; Dashkevich, V. I.; Orlovich, V. A.; Yasukevich, A. S.; Kuleshov, N. V.; Yumashev, K. V.; Grigoriev, S. V.; Vatnik, S. M.; Bagaev, S. N.; Pavlyuk, A. A. (2016)
      We report on growth and detailed spectroscopic study of Eu3ю-doped tetragonal sodium gadolinium double tungstate, Eu:NaGd(WO4)2, a new promising crystal for deep-red lasers. Large-volume crystal doped with 4.9 at.% Eu is grown by Czochralski method along the [001] crystallographic direction. Absorption of Eu3ю ions is studied at room temperature (RT) and at 6 K. For the absorption ...
      2017-11-18

    • Thermal lens study in diode pumped Ng- and Np-cut Nd:KGd(WO4)2 laser crystals 

      Loiko, P. A.; Yumashev, K. V.; Kuleshov, N. V.; Savitski, V. G.; Calvez, S.; Burns, D.; Pavlyuk, A. A. (Optical Society of America, 2009)
      A comparative study of thermal lensing effect in diode laser pumped Ng- and Np-cut Nd:KGd(WO4)2 (KGW) laser crystals was performed for laser emission polarized along the principle refractive axis, Nm. The thermal lens in the Ng-cut Nd: KGW was found to be weakly astigmatic with a positive refractive power for both the Nm- and Np-directions. For Np -cut Nd:KGW, strong astigmatism ...
      2012-01-24

    • Thermal lensing measurements in the anisotropic laser crystals under diode pumping 

      Loiko, P. A.; Savitski, V. G.; Yumashev, K. V.; Kuleshov, N. V.; Pavlyuk, A. A. (БНТУ, 2012)
      An experimental setup was developed for thermal lensing measurements in the anisotropic di-ode-pumped laser crystals. The studied crystal is placed into the stable two-mirror laser cavity operating at the fundamental transversal mode. The output beam radius is measured with re-spect to the pump intensity for different meridional planes (all these planes contain the light propagation ...Nm.
      2013-02-05