Now showing items 1-20 of 21

    • 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 ...
      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
    • Compact 0.7 mJ/11 ns eye-safe erbium laser 

      Vitkin, V. V.; Polyakov, V. M.; Kharitonov, A. A.; Buchenkov, V. A.; Rodionov, A. Yu.; Zhilin, A. A.; Dymshits, O. S.; Loiko, P. A. (2016)
      We report on the development of a compact diode-end-pumped eye-safe (similar to 1.54 mu m) passively-cooled Er, Yb:glass laser. The design of this laser is facilitated by the use of a double-pass pumping scheme and a special ZrO2 diffuse reflector for a uniform pump distribution. In the free-running mode, this laser generates 8.2 mJ/3 ms pulses with a slope efficiency of 15%. ...
      2018-02-27
    • Continuous-wave Tm:KY(WO4)2 waveguide laser 

      Kifle, E.; Mateos, X.; Aguilo, M.; Diaz, F.; Loiko, P. A.; Yumashev, K. V. (БНТУ, 2016)
      Continuous-wave Tm:KY(WO4)2 waveguide laser / E. Kifle [et al.] // Новые направления развития приборостроения : материалы 9-й международной научно-технической конференции молодых ученых и студентов, Минск, 20–22 апреля 2016 г. : в 2 т. / Белорусский национальный технический университет ; редкол.: О. К. Гусев [и др.]. – Минск, 2016. – Т. 2. - С. 30.
      2016-09-22
    • Cooperative up-conversion in Eu3+,Yb3+-doped SiO2–PbO–PbF2–CdF2 oxyfluoride glass 

      Loiko, P. A.; Rachkovskaya, G. E.; Zakharevich, G. B.; Kornienko, A. A.; Dunina, E. B.; Yasukevich, A. S.; Yumashev, K. V. (Elsevier, 2014)
      Novel oxy fluoride glass doped with YbF3 and Eu2O3 is synthesized in the SiO2–PbO–PbF2–CdF2 system by melt quenching technique. Its physical properties, as well as the optical absorption of Eu3+ and Yb3+ ions are studied. Spectroscopic properties of Eu3+ ions are modeled within modified Judd–Ofelt theory, yielding absorption oscillator strength, luminescence branching ratios and ...
      2016-01-05
    • CW Tm:KLu(WO4)2 microchip laser 

      Loiko, P. A.; Serres, J. M.; Mateos, X.; Yumashev, K. V.; Kuleshov, N. V.; Petrov, V.; Griebner, U.; Aguilo, M.; Diaz, F. (БНТУ, 2014)
      CW Tm:KLu(WO4)2 microchip laser / P. A. Loiko [и др.] // Приборостроение-2014 : материалы 7-й Международной научно-технической конференции (19–21 ноября 2014 года, Минск, Республика Беларусь) / ред. колл.: О. К. Гусев [и др.]. – Минск : БНТУ, 2014. – С. 231 - 232.
      2015-03-19
    • 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
    • Graphene Q-switched waveguide laser at 1.83 μm 

      Kifle, E.; Mateos, X.; Loiko, P. A.; Yumashev, K. V.; Petrov, V.; Griebner, U.; Aguilo, M.; Diaz, F. (БНТУ, 2016)
      Graphene Q-switched waveguide laser at 1.83 μm / E. Kifle [et al.] // Приборостроение-2016 : материалы 9-й международной научно-технической конференции, Минск, 23-25 ноября 2016 г. / Белорусский национальный технический университет ; редкол.: О. К. Гусев [и др.]. – Минск, 2016. – С. 236-237.
      2017-03-23
    • Ho:KLuW laser passively q-switched by a PbS quantum dot-doped glass 

      Serres, J. M.; Mateos, X.; Aguilo, M.; Diaz, F.; Loiko, P. A.; Malyarevich, A. M.; Yumashev, K. V. (БНТУ, 2016)
      Ho:KLuW laser passively q-switched by a PbS quantum dot-doped glass / J. M. Serres [et al.] // Новые направления развития приборостроения : материалы 9-й международной научно-технической конференции молодых ученых и студентов, Минск, 20–22 апреля 2016 г. : в 2 т. / Белорусский национальный технический университет ; редкол.: О. К. Гусев [и др.]. – Минск, 2016. – Т. 2. - С. 57.
      2016-09-23
    • Ho:KLuW microchip laser intracavity pumped by a diode-pumped Tm:KLuW laser 

      Serres, J. M.; Loiko, P. A.; Mateos, X.; Yumashev, K. V.; Kuleshov, N. V.; Petrov, V.; Griebner, U.; Aguilo, M.; Diaz, F. (Springer, 2015)
      A compact intracavity-pumped microchip Ho laser is realized using stacked Tm:KLuW/Ho:KLuW crystals pumped by a laser diode at 805 nm; both crystals are cut for light propagation along the Ng optical indicatrix axis and emit with polarization along the Nm axis. Maximum CW output power of 285 mW is achieved at a wavelength of 2080 nm for 5.6 W absorbed pump power in the Tm:KLuW ...
      2018-09-14
    • Luminescence of oxyfluoride glasses containing YB3+–RE3+ ions 

      Loiko, P. A.; Rachkovskaya, G. E.; Zakharevich, G. B.; Skoptsov, N. A.; Yumashev, K. V. (2016)
      The optical absorption and up-conversion luminescence of oxyfluoride glasses in the system SiO2–PbO–PbF2–CdF2 coactivated by Yb3+–RE3+ ions (where RE = Er, Tm, Ho, Dy, Pr, or Tb) are investigated. Excitation with a laser diode in the IR range (960 nm) gives intense green, blue, and red luminescence. The color characteristics of the up-conversion luminescence in the CIE 1931 system ...
      2017-11-22
    • Passive Q-switching of a Tm,Ho:KLu(WO4)2 microchip laser by a Cr:ZnS saturable absorber 

      Serres, Y. M.; Loiko, P. A.; Mateos, X.; Jambunathan, V.; Yasukevich, A. S.; Yumashev, K. V.; Petrov, V.; Griebner, U.; Aguilo, M.; Diaz, F. (Optical Society of America, 2016)
      A diode-pumped Tm;Ho:KLu WO42 microchip laser passively Q-switched with a Cr:ZnS saturable absorber generated an average output power of 131 mW at 2063.6 nm with a slope efficiency of 11% and a Q-switching conversion efficiency of 58%. The pulse characteristics were 14 ns∕9 μJ at a pulse repetition frequency of 14.5 kHz. With higher modulation depth of the saturable absorber, 9 ...
      2016-05-12
    • Passive Q-switching of Yb bulk lasers by a graphene saturable absorber 

      Loiko, P. A.; Serres, J. M.; Mateos, X.; Liu, G.; Zhang, H.; Yasukevich, A. S.; Yumashev, K. V.; Petrov, V.; Griebner, U.; Aguilo, M.; Diaz, F. (Springer, 2016)
      Compact Yb:KLu(WO4)2 and Yb:LuVO4 lasers diode-pumped at 978 nm are passively Q-switched by a single-layer graphene saturable absorber. The Yb:KLu(WO4)2 laser generated 165 ns/0.49 μJ pulses at 1030 nm with 170 mW average output power and 12 % slope efficiency. With the Yb:LuVO4 laser, 152 ns/0.83 μJ pulses were achieved. The output power reached 300 mW at 1024 nm, and the slope ...
      2016-05-11
    • 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
    • Stokes and anti-Stokes luminescence from cubic elpasolite Cs2NaYF6 crystals doped with Er3+and Yb3+ ions 

      Loiko, P. A.; Khaidukov, N. M.; Mendez-Ramos, J.; Vilejshikova, E. V.; Skoptsov, N. A.; Yumashev, K. V. (Elsevier, 2016)
      Er3þ and Yb3þ doped cubic elpasolite Cs2NaYF6 crystals including stoichiometric compositions Cs2NaErF6 and Cs2NaYbF6 have been synthesized under hydrothermal conditions. Absorption, stimulated-emission and gain cross-sections spectra have been determined for the 2F5/2-2F7/2 (Yb3þ) and 4I13/2-4I15/2 (Er3þ) transitions at room-temperature. The maximum σSE values are 1.8 10 21 cm2 ...
      2016-05-12
    • Structure and nonlinear optical properties of novel transparent glass-ceramics based on Co2+:ZnO nanocrystals 

      Loiko, P. A.; Dymshits, O. S.; Vitkin, V. V.; Skoptsov, N. A.; Zhilin, A. A.; Shemchuk, D. V.; Tsenter, M. Ya.; Bogdanov, K. V.; Malyarevich, A. M.; Glazunov, I. V.; Mateos, X.; Yumashev, K. V. (2016)
      Transparent glass-ceramics (GCs) based on Co2+:ZnO nanocrystals (mean diameter, 11 nm) are synthesized on the basis of cobalt-doped glasses of the K2O–ZnO–Al2O3–SiO2 system. For these GCs, the absorption band related to the 4A2(4F) → 4T1(4F) transition of Co2+ ions in tetrahedral sites spans until ~1.73 μm. Saturation of the absorption is demonstrated at 1.54 μm, with a saturation ...
      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
    • Thermo-optic properties of Yb:Lu2O3 single crystals 

      Loiko, P. A.; Yumashev, K. V.; Schödel, R.; Peltz, M.; Liebald, C.; Mateos, X.; Deppe, B. (Springer, 2015)
      A detailed study of thermo-optic properties of 1.5 at.% Yb:Lu2O3 single crystal is performed. Thermo-optic dispersion formulas are derived for dn/dT coefficient and thermal coefficient of the optical path. At the wavelength of 1.03 μm, dn/dT = 5.8 × 10−6 K−1. High-precision temperature-dependent measurements of the thermal expansion coefficient α are performed. At the room ...
      2018-09-17