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

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 energy level, were determined

Micro-crystallization and spectroscopic properties of Er, Yb:RAl-borates (R=Y, Gd) obtained in RAl<inf>3</inf>(BO<inf>3</inf>)<inf>4</inf>–K<inf>2</inf>Mo<inf>3</inf>O<inf>10</inf>–B<inf>2</inf>O<inf>3</inf>–R<inf>2</inf>O<inf>3</inf> and RAl<inf>3</inf>(BO<inf>3</inf>)<inf>4</inf>–B<inf>2</inf>O<inf>3</inf> systems

© 2016 Elsevier B.V.The spontaneous YAl3(BO3)4 (YAB) and GdAl3(BO3)4 (GdAB) crystals (of nominal composition and co-doped with Er and Yb) up to 4–5 mm in length were grown from high-temperature solutions using K2Mo3O10 based fluxes in the temperature range of 1120–900 °C. Glass–ceramic composites based on the YAB and GdAB micro-crystals have been prepared by quenching YAB–B2O3 and GdAB–B2O3 melts and characterized by X-ray diffraction and spectroscopic methods. The vitrified melt was shown to contain micro- and nano-crystalline rare-earth borate phases. Their distribution over the composites has been investigated by electron microscopy and three-dimensional X-ray tomography. The absorption spectra of these materials co-doped with erbium and ytterbium as well as luminescence spectrum were demonstrated

Micro-crystallization and spectroscopic properties of Er, Yb:RAl-borates (R=Y, Gd) obtained in RAl<inf>3</inf>(BO<inf>3</inf>)<inf>4</inf>-K<inf>2</inf>Mo<inf>3</inf>O<inf>10</inf>-B<inf>2</inf>O<inf>3</inf>-R<inf>2</inf>O<inf>3</inf> and RAl<inf>3</inf>(BO<inf>3</inf>)<inf>4</inf>-B<inf>2</inf>O<inf>3</inf> s

© 2016 Elsevier B.V.The spontaneous YAl3(BO3)4 (YAB) and GdAl3(BO3)4 (GdAB) crystals (of nominal composition and co-doped with Er and Yb) up to 4-5mm in length were grown from high-temperature solutions using K2Mo3O10 based fluxes in the temperature range of 1120-900°C. Glass-ceramic composites based on the YAB and GdAB micro-crystals have been prepared by quenching YAB-B2O3 and GdAB-B2O3 melts and characterized by X-ray diffraction and spectroscopic methods. The vitrified melt was shown to contain micro- and nano-crystalline rare-earth borate phases. Their distribution over the composites has been investigated by electron microscopy and three-dimensional X-ray tomography. The absorption spectra of these materials co-doped with erbium and ytterbium as well as luminescence spectrum were demonstrated

Highly efficient continuous-wave diode-pumped Er, Yb:GdAl3(BO3)4 laser

We report the highly efficient continuous-wave diode-pumped laser operation of Er, Yb:GdAl3 BO3 4 crystal. Absorption and stimulated emission spectra, emission lifetimes, and efficiencies of energy transfer from Yb3 to Er3 ions were determined. A maximal output power of 780 mWwas obtained at 1531 nm at absorbed pump power of 4 W with slope efficiency of 26%

Spectroscopy and laser performance of in-band pumped Er:LLF and Er:YLF crystals

© 2016 IEEE.Spectroscopic properties and continuous-wave laser performance of in-band pumped Er:LiLuF4 and Er:LiYF4 crystals were investigated. For Er:LiLuF4 crystal maximum slope efficiency of 44 % was obtained at 1609 nm wavelength. Er:LiYF4 crystal laser operation was demonstrated for the first time under in-band pumping. Output power of 58 mW and slope efficiency of 21 % at 1606 nm were achieved

Laser Performance of Er,Yb:YAl3(BO3)4 Crystals with Different Erbium Concentrations

The effect of erbium concentration on the laser performance of Er,Yb:YAl3(BO3)4 crystals was investigated. A maximal output power of 1.6 W in CW and 2.7 W in QCW regimes was obtained at 1522 nm

Er:KY(WO42 and Er:LiYF4 crystals for eye-safe in-band pumped lasers

© OSA 2015. Laser operation of in-band pumped Er:KY(WO4)2 and, for the first time to our knowledge, Er:LiYF4 crystals was demonstrated. The maximal slope efficiencies of 40% and 21% were obtained for Er:KY(WO4)2 and Er:LiYF4 crystals, respectively

Laser performance of in-band pumped Er : LiYF4 and Er : LiLuF4 crystals

Spectroscopic properties of Er : LiLuF4 and Er : LiYF4 crystals in the spectral region near 1.5 mm and the lasing characteristics of these crystals under in-band pumping at a wavelength of 1522 nm are studied. With the Er : LiLuF4 crystal, the maximum slope efficiency with respect to the absorbed pump power was 44 % at a wavelength of 1609 nm. Continuous-wave operation of an in-band pumped Er : LiYF4 laser is obtained for the first time. The output power at a wavelength of 1606 nm was 58 mW with a slope efficiency of 21%

Кристаллы Er,Yb:Ca3RE2(BO3)4 (RE=Y, Gd) – новые среды для лазеров, излучающих в спектральном диапазоне 1,5 мкм

The search for new crystalline host materials for the usage in lasers emitting in the eye-safe spectral range of 1.5–1.6 µm is an important task. The aim of this work was to study the growth technique, spectroscopic properties and laser characteristics of new active media – crystals Er3+,Yb3+:Ca2RE2(BO3)4 (RE=Y, Gd).Calcium-yttrium Er3+,Yb3+:Ca3Y2 (BO3)4 (CYB) and calcium-gadolinium Er3+,Yb3+: Ca2 Gd 2(BO3)4  (CGB) oxoborate crystals co-doped with erbium and ytterbium ions were investigated. Polarized absorption and emission cross-section spectra were determined. The lifetimes of 4I11/2 and 4I13/2 energy levels of Er3+ ions were measured and ytterbium-erbium energy transfer efficiencies were estimated. The calculation of the gain cross-section spectra was performed. By using of Er3+,Yb3+: Ca2 RE 2(BO3)4  (RE=Y, Gd) crystals the laser performance was realized, for the first time to the best of our knowledge. The laser characteristics were studied in a quasi-CW (QCW) laser operation.The wide band with a peak at the wavelength of 976 nm is observed in the absorption spectra of both crystals. This peak coincides with the emission wavelength of the pump laser diodes for Yb-doped active media. The maximum value of absorption cross-section was 1.7 × 10–20 cm2 for polarization E // b for both crystals. The lifetimes of the upper laser level 4I13/2 of Er3+ ions were 580 ± 30 μs and 550 ± 30 μs for Er,Yb:CYB and Er,Yb:CGB crystals, respectively. The energy transfer efficiencies from ytterbium to erbium ions for an Er,Yb:CYB and Er,Yb:CGB crystals were 94 % and 96 %, respectively. According to gain spectrum of the Er,Yb:CYB crystal the gain band peak is centered at the wavelength of 1530 nm. The maximum QCW output power was 0.5 W with slope efficiency of 13 % regarding to absorbed pump power for an Er,Yb: CYB crystal. The laser beam parameter M2 did not exceed &lt; 1.5.Based on the obtained results, it can be concluded that these crystals are promising active media for lasers emitting in the spectral range of 1.5–1.6 μm for the usage in laser rangefinder and laser-induced breakdown spectroscopy systems, and LIDARs.Поиск новых кристаллических матриц для применения в лазерах, излучающих в условно безопасном для глаз спектральном диапазоне 1,5–1,6 мкм, является актуальной задачей. Целью данной работы являлось изучение технологии роста, спектроскопических свойств и генерационных характеристик новых активных сред – кристаллов Er3+,Yb3+:Ca2RE2(BO3)4  (RE=Y, Gd).В качестве исследуемых образцов использовались кристаллы кальций-иттриевого Er3+,Yb3+:Ca3Y2(BO3)4 (CYB) и кальций-гадолиниевого Er3+,Yb3+: Ca2 Gd 2(BO3)4  (CGB) оксоборатов, соактивированных ионами эрбия и иттербия. В результате определены спектры поперечных сечений поглощения и стимулированного испускания в поляризованном свете. Определены времена жизни энергетических уровней 4I11/2 и 4I13/2 иона эрбия, а также проведена оценка эффективности переноса энергии от ионов иттебрия к ионам эрбия. Выполнен расчет спектров поперечных сечений усиления. Впервые с использованием кристаллов реализована лазерная генерация, изучены генерационные характеристики в квазинепрерывном режиме генерации.В спектрах поглощения для обоих кристаллов наблюдается полоса с пиком на длине волны 976 нм, что согласуется с длиной волны испускания лазерных диодов, применяемых для накачки активных элементов с ионами Yb3+ . Наибольшее значение поперечного сечения поглощения для обоих кристаллов составило 1,7×10–20 см2 для поляризации E // b на длине волны 976 нм. Время жизни верхнего лазерного уровня 4I13/2 составило 580 ± 30 мкс и 550 ± 30 мкс для кристаллов Er,Yb:CYB и Er,Yb:CGB соответственно. Эффективность переноса энергии от ионов иттербия к ионам эрбия составила 94 % для кристалла Er,Yb:CYB и 96 % для Er,Yb:CGB. Расчет спектра усиления для кристалла Er,Yb:CYB, показал что максимум полосы усиления находится на длине волны 1530 нм. Максимальное значение выходной мощности в квазинепрерывном режиме генерации составило 0,5 Вт при дифференциальной эффективности по поглощенной мощности накачки 13 % для кристалла Er,Yb:CYB, параметр распространения лазерного пучка М2 не превышал 1,5.На основе полученных результатов, можно сделать вывод, что данные кристаллы являются перспективными активными средами для лазеров, излучающих в спектральном диапазоне 1,5–1,6 мкм, для применения в составе систем лазерной дальнометрии, лазерно-искровой эмиссионной спектрометрии и лидаров