N. A. Tolstik

Spectroscopy and continuous-wave diode-pumped laser action of Yb 3+ :YVO 4

The growth, spectroscopic properties, and laser performance of Yb:YVO4 crystal with laser diode pumping are reported. A peak absorption cross section of 7.4 x 10(-20) cm2 at 985 nm, a radiative lifetime of 0.25 ms, and a stimulated-emission cross section of 1.25 x 10(-20) cm2 at 1008 nm for pi polarization were determined for the Yb3+ ions in YVO4. Continuous-wave laser action of Yb:YVO4 at 1020-1027 nm was demonstrated with an output power of 610 mW and a slope efficiency of 49%.

Efficient 1 W continuous-wave diode-pumped Er,Yb:YAl3(BO3)4 laser

We report the spectroscopy and high-power continuous-wave (CW) diode-pumped laser operation of Er:Yb:YAl3(BO3) crystal. Absorption and stimulated emission spectra, emission lifetimes, and efficiency of energy transfer from Yb3+ to Er3+ ions were determined. A CW Er:Yb:YAB laser emitting at 1602, 1555, and 1531 nm with output power as high as 1W and slope efficiency up to 35% was demonstrated.

Diode-pumped passively mode-locked Er,Yb:YAl 3 (BO 3 ) 4 laser at 1.5-1.6 μm

This paper reports on a passively mode-locked Er³⁺,Yb³⁺:YAl₃(BO₃)₄ (Er,Yb:YAB) laser that generates 3.8 ps-pulses at 1530 nm with an average power up to 270 mW. This is the first passively mode-locked Er /Yb co-doped laser based on a crystalline gain medium. The optimisation of the saturable absorber and laser-gain parameters such as modulation depth, intracavity fluence and dispersion will lead to efficient sub-picosecond pulse generation in range of 1.5-1.6 μm from this type of diode-pumped Er,Yb:YAB laser.

Liquid-phase epitaxy of single-crystal erbium-ytterbium codoped YAl3(BO3)4 layers as key components of planar waveguides

YAl3(BO3)4 (YAB) crystals 10 × 10 × 8 mm in dimensions were grown on point seeds from a potassium-trimolybdate-based high-temperature solution. The crystals were used as substrates for liquid-phase epitaxy of (Er,Yb):YAB single-crystal films 50 to 100 μm in thickness. The hexagonal cell parameters of nominally undoped and erbium-ytterbium codoped YAB were determined as functions of temperature by high-temperature X-ray diffraction and were used to evaluate the thermal expansion coefficients of the materials. We have demonstrated waveguiding and measured the optical loss in the films.

Energy transfer between Yb3+ and Er3+ ions in an Er,Yb:YAl3(BO3)4 crystal

The electron-excitation energy transfer between Er3+ and Yb3+ ions in Er,Yb:YAl3(BO3)4 crystals has been investigated. Crystals with different concentrations of active ions have been grown, and their luminescence decay kinetics in the spectral range near 1 μm have been experimentally measured. The energy-transfer microparameters have been calculated. It is shown that, to correctly describe the energy transfer in Er,Yb:YAl3(BO3)4 crystals, one must take into account the interactions of higher orders than dipole-dipole interactions.

Growth of (Er,Yb):YAl3(BO3)4 laser crystals

Abstract(Er,Yb):YAl3(BO3)4 single crystals of optical quality, up to 15 × 10 × 10 mm3 in size, have been grown from a (Er0.023Yb0.116Y0.862)Al3(BO3)4 solution in a Y2O3-B2O3-K2Mo3O10 melt. The initial borate concentration was 17 wt %, and the flux cooling rate increased from 0.08 to 0.12°C/h in the range 1060–1000°C. The physical properties of the single crystals grown are good enough that they can be used as laser elements in systems with diode pumping and radiation near 1.5 μm.

Growth and spectroscopic characterization of Cr:ZnTe laser crystals

Here we report on crystal growth and detailed investigation of spectroscopic properties of Cr-doped ZnTe single crystal, Cr:ZnTe, for the first time reported in, remained so far fairly unstudied inspite of its large potential (due to the existing thin film technology of ZnTe) as a material for various laser- and nonlinear-optical applications. The first studies of Cr:ZnTe were done on the crystals without any postgrowth treatment. However, in this work we established a strong dependence of spectroscopic properties on the growth and postgrowth treatment conditions. Understanding of the involved physical mechanisms should finally pave the route towards an optimized laser quality Cr:ZnTe.

Er,Yb:YAB laser with high output power

In this work we present spectroscopy, continuous-wave (cw) and Q-switched laser operation of Er,Yb-codoped YAl3(BO3)4 (Er,Yb:YAB) crystal under diode pumping. Single crystal of Er(1 at.%),Yb(11 at.%):YAB with dimensions of 15times15times20 mm was grown by the TSSG method using K2Mo3O10 based fluxes. The concentration of the dopants was measured by microprobe analysis. In conclusion, spectroscopic properties and CW and passively Q-switched diode-pumped laser performance of Er,Yb-codoped YAB crystals have been characterized. The results of laser experiments with more powerful diode pumping and cw output power exceeding 300 mW will be presented at the conference. Laser experiments were performed with a nearly hemispherical cavity consisting of 50-mm radius-of-curvature output coupler and plane high reflector.

Inband Pumped Er:Lu 2 O 3 and (Er,Yb):YVO 4 Lasers near 1.6 µm for CO 2 LIDAR

Er:Lu2O3 and (Er,Yb):YVO4 provide suitable spectra for CO2-LIDAR systems around 1.6µm. First inband pumped laser experiments show output powers up to 1.26W and slope efficiencies of up to 48% with respect to absorbed pump power.

Growth of (Er,Yb):YAl{sub 3}(BO{sub 3}){sub 4} laser crystals

Abstract(Er,Yb):YAl3(BO3)4 single crystals of optical quality, up to 15 × 10 × 10 mm3 in size, have been grown from a (Er0.023Yb0.116Y0.862)Al3(BO3)4 solution in a Y2O3-B2O3-K2Mo3O10 melt. The initial borate concentration was 17 wt %, and the flux cooling rate increased from 0.08 to 0.12°C/h in the range 1060–1000°C. The physical properties of the single crystals grown are good enough that they can be used as laser elements in systems with diode pumping and radiation near 1.5 μm.