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Highlights: [•] Spectroscopic properties and crystal growth of Tm:LYSO single crystal were studied for the first time. [•] The large absorption and emission cross-section and broad FWHM make Tm:LYSO a promising media for tunable and ultrashort pulses. [•] The J–O parameters and gain spectra reveal that the excellent properties for laser applications. [Copyright &y& Elsevier]

Abstract: Yb3+-doped (Lu0.5Y0.5)3Al5O12 (Yb:LuYAG) single crystal has been grown by the Czochralski method. The segregation coefficient of Yb3+ was studied by the inductively coupled plasma atomic emission spectrometry (ICP-AES) method. The crystal structure has been determined by X-ray diffraction analysis. The absorption and emission spectra and fluorescence lifetime of Yb:LuYAG crystal were measured at room temperature. The spectroscopic parameters of Yb:LuYAG crystal were compared with those of Yb:YAG and Yb:LuAG crystals with the same doping level. The results indicate that Yb:LuYAG crystals are potential candidates for high-power ultrashort pulse lasers. [ABSTRACT FROM AUTHOR]

Abstract: A Yb3+-doped CaYAlO4 laser crystal has been grown by the Czochralski technique. The segregation coefficient was measured by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). The cell parameters were analyzed with X-ray diffraction experiments. Color defects in Yb:CaYAlO4 have been evidenced to be similar to those in undoped CaYAlO4. The polarized absorption spectra and the fluorescence spectrum of the Yb:CaYAlO4 crystal were measured at room temperature. The fluorescence decay time of the Yb3+ ion was investigated. The results show that Yb:CaYAlO4 has potential as a laser gain medium for an ultrashort laser system. [Copyright &y& Elsevier]

Abstract: A high optical quality erbium doped Lu2SiO5 single crystal has been grown by the Czochralski method. The distribution coefficient of Er3+ was measured to be ∼0.926. The absorption and emission spectra as well as the fluorescence decay curve of the excited state 4I13/2 were measured at room temperature. The spectroscopic parameters were calculated using the Judd–Ofelt theory, and the J–O parameters Ω 2 , Ω 4 and Ω 6 were found to be 4.451×10-20, 1.614×10-20 and 1.158×10-20 cm2, respectively. The room-temperature fluorescence lifetime of the Er3+ 4I13/2→4I15/2 transition was measured to be 7.74ms. The absorption and emission cross-section as well as the gain cross-section in the eye-safe regime of 1400–1700nm were also determined and discussed. [Copyright &y& Elsevier]

Abstract Nd3+-doped Bi 4 Ge 3 O 12 (Nd:BGO) single crystals have been successfully grown by the micro-pulling-down (μ-PD) method. The absorption spectra, fluorescence spectra and fluorescence decay curve have been measured at room temperature. The absorption cross section is about 1.39 × 10–20 cm2 at around 808 nm for 0.3 at% Nd:BGO. The Judd–Ofelt theory has been applied to calculate the intensity parameters, and three spectroscopic parameter Ω t (t = 2,4,6), radiative transition probabilities, radiative lifetime and branching ratios were calculated. The stimulated emission cross-section of 4F 3/2 →4I 11/2 transition at 1064 nm was obtained to be 3.29 × 10–20 cm2 for 0.3 at% Nd3+-doped BGO crystal. The fluorescence lifetimes of 0.3 at% and 1.0 at% neodymium-doped BGO crystals were measured to be 288 μs and 242 μs, respectively. Those results indicate that Nd3+-doped BGO crystal grown by the μ-PD method would be a potential laser medium. [ABSTRACT FROM AUTHOR]

Tb 3+ -doped YAlO 3 (YAP) single crystal was grown by Czochralski (Cz) method. Based on the polarized absorption spectra, the spectroscopic parameters were calculated to be Ω 2 = 3.49 × 10 −20 cm 2 , Ω 4 = 5.87 × 10 −20 cm 2 and Ω 6 = 2.55 × 10 −20 cm 2 , and then the spontaneous transition rate, fluorescent branching ratio and radiative lifetime of 5 D 4 multiplet were obtained. The yellow emission cross sections of 5 D 4 → 7 F 4 transition were calculated to be 1.72 × 10 −22 cm 2 , 2.73 × 10 −22 cm 2 and 2.65 × 10 −22 cm 2 for a, b and c polarization, respectively. The fluorescence lifetime of the 5 D 4 multiplet was fitted to be 1.72 ms. All the data indicate that Tb:YAP crystal is a promising candidate for yellow laser operation. [ABSTRACT FROM AUTHOR]

Ho3+-doped CaY 0.9 Gd 0.1 AlO 4 single crystal was successfully grown by the Czochralski technique for the first time. The polarized absorption spectra, polarized luminescence spectra and fluorescence decay curve of the crystal were investigated at room temperature. The spectroscopic parameters are calculated based on Judd–Ofelt theory, the values of Ω 2,4,6 were calculated to be 3.16 × 10−20 cm2, 3.93 × 10−20 cm2, 0.91 × 10−20 cm2, respectively. The Ho:CaY 0.9 Gd 0.1 AlO 4 crystal exhibits strong emission at 2013 nm for π- and 2032 nm for σ-polarizations with stimulated emission cross section of 6.64 × 10−20 cm2 and 1.90 × 10−20 cm2, respectively. The fluorescence lifetime of the 5I 7 level was measured to be 6.60 ms. The continuous-wave (CW) laser operation of Ho:CaY 0.9 Gd 0.1 AlO 4 crystal around 2 μm was demonstrated. • Ho3+-doped CaY 0.9 Gd 0.1 AlO 4 single crystal was successfully grown by the Czochralski technique for the first time. • The emission cross-section at 2013 nm and 2032 nm are 6.64 × 10−20 cm2 and 1.90 × 10−20 cm2 for π- and σ-polarizations respectively. • The continuous-wave (CW) laser operation of Ho:CaY 0.9 Gd 0.1 AlO 4 crystal around 2 μm was demonstrated. [ABSTRACT FROM AUTHOR]

LaMgAl 11 O 19 (LMA) crystal with nominal Sm3+ concentrations of 8 at.% was grown by the Czochralski method. Polarized absorption spectra, polarized emission spectra and fluorescence decay curve of Sm:LMA crystal were recorded at room temperature. The absorption cross-sections at 404 nm were calculated to be 2.33 × 10−20 cm2 and 0.86 × 10−20 cm2 for σ and π polarization, respectively. The spontaneous transition rates, branching ratios and the radiative lifetime of the 4G 5/2 multiplet, were calculated. The Judd-Ofelt theory has been applied to evaluate the Ω t (t = 2, 4, 6) intensity parameters. The highest stimulated emission cross-sections for the 4G 5/2 → 6H 7/2 transition around 594 nm were calculated to be 1.67 × 10−21 cm2 for σ polarization and 1.15 × 10−21 cm2 for π polarization, with full width at half maximum (FWHM) of 7.68 nm and 7.27 nm, respectively. The fluorescence lifetime of the 4G 5/2 manifold was 1.84 ms. All the results show that Sm:LMA crystal would be a promising orange-red solid state laser material. • The most intensive absorption line of Sm3+ ion, suitable for 405 nm InGaN laser diode. • The rigidity of Sm:LMA crystal is higher than some host crystals. • The value Ω 2 of Sm:LMA crystal is comparable to Sm:LiYF 4. • The large parameter σ em τ of Sm3+ in LMA is beneficial for the solid state laser. [ABSTRACT FROM AUTHOR]