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The crystal growth, polarized spectral properties, Judd-Ofelt (JO) analysis and lifetime of Sm:CaGdAlO 4 (Sm:CGA) crystal were reported for the first time. Sm:CGA crystal with size of Φ4 × 33 mm 3 was grown by the floating zone (FZ) method. The peak absorption cross-sections at 407 nm were calculated to be 3.41 × 10 −20 cm 2 and 3.20 × 10 −20 cm 2 for the σ and π polarization, and the largest stimulated emission cross-sections at 601 nm were 5.10 × 10 −21 cm 2 and 4.66 × 10 −21 cm 2 , respectively. The absorption and emission cross-sections were several times larger than that of Sm:LiYF 4 . The JO intensity parameters of Ω 2 , Ω 4 and Ω 6 were calculated to be 3.0 × 10 −20 cm 2 , 6.1 × 10 −20 cm 2 and 6.5 × 10 −20 cm 2 , respectively. The lifetime of the 4 G 5/2 level was obtained to be 0.69 ms. All the results indicate that Sm:CGA crystal is a potential laser host for the reddish-orange laser operation. [ABSTRACT FROM AUTHOR]

The crystal growth, optical spectra and lifetime of Dy:CaGdAlO 4 crystal were investigated for the first time to our best knowledge. Single Dy:CaGdAlO 4 crystal with size of Φ4 × 40 mm 3 was grown by floating zone method. The peak absorption cross-sections were calculated to be 2.43 × 10 −21 cm 2 and 1.28 × 10 −21 cm 2 at 453 nm for σ and π polarizations. The Judd-Ofelt (JO) parameters of Ω 2 , Ω 4 and Ω 6 were calculated to be 1.8 × 10 −20 cm 2 , 1.0 × 10 −20 cm 2 and 0.5 × 10 −20 cm 2 , respectively. The emission cross-sections were calculated to be 0.51 × 10 −20 cm 2 and 0.55 × 10 −20 cm 2 for σ and π polarizations. The fluorescence decay time is 222 μs. The results indicate that the Dy:CaGdAlO 4 crystal is a potential candidate for yellow laser operation. [ABSTRACT FROM AUTHOR]

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]

Yb:CaYAlO 4 (Yb:CALYO) shaped crystal fibers with different Yb3+ doping concentration were successfully grown by the micro-pulling-down (μ -PD) method. The effect of the Yb3+ concentration on the structure, absorption, emission and lifetime was systematically studied. The strongest absorption peaks of Yb:CALYO crystal fibers are located at 977 nm for σ and π polarization. The micro-photoluminescence indicate that Yb3+ ions in CALYO single crystal fiber grown by the μ -PD method distributed evenly across a cross-section. The emission cross-section of 5 at.% Yb:CALYO crystal fiber was calculated to be 0.86 × 10−20 and 1.08 × 10−20 cm2 at 983 nm for σ and π polarizations. Benefited from the disordered structrure of CaYAlO 4 crystal, the full width at half maximum (FWHM) at 978 nm was 68.9 nm and 80.9 nm, respectively. The fluorescence lifetime of 2F 5/2 energy level of Yb:CALYO crystal fibers with concentration of 0.5 at.%, 1 at.%, 2 at.% and 5 at.% was calculated to be 435 μs, 484 μs, 514 μs and 453 μs, respectively. The experimental results show that Yb:CALYO crystal fiber is a potential laser medium for ultrashort laser operation. • Yb:CaYAlO 4 shaped crystal fibers were grown by the micro-pulling down method. • The crystal structure, polarized spectra were investigated. • The effect of Yb3+ concentration on the spectroscopic properties was evaluated. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, single crystal of ytterbium (Yb) doped Ca5(PO4)3F (FAP) has been grown along the c-axis by using the Czochralski method. The segregation coefficients of Yb3+ in the Yb:FAP crystal has been determined by ICP-AES method. The absorption spectrum, fluorescence spectrum and fluorescence lifetime of the Yb:FAP crystal has been also measured at room temperature. In the absorption spectra, there are two absorption bands at 904 and 982nm, respectively, which are suitable for InGaAs diode laser pumping. The absorption cross-section (σ abs) is 5.117×10−20 cm2 with an FWHM of 4nm at 982nm. The emission cross-section (σ em) is 3.678×10−20 cm2 at 1042nm. Favorable values of the absorption cross-section at about 982nm are promising candidates for laser diode (LD) pumping. [Copyright &y& Elsevier]

Sm:YAlO 3 (Sm:YAP) crystal with size of Φ28 × 80 mm3 was grown by Czochralski (Cz) method. Polarized absorption spectra and fluorescence spectra of Sm:YAP crystal were discussed for the first time. The peak emission cross-sections were calculated to be 0.80 × 10−21 cm2 (604 nm for a-polarization), 1.82 × 10−21 cm2 (604 nm for b-polarization) and 1.63 × 10−21 cm2 (610 nm for c-polarization), respectively. The Judd-Ofelt (JO) intensity parameters were calculated to be Ω 2 = 2.59 × 10−20 cm2, Ω 4 = 1.78 × 10−20 cm2 and Ω 6 = 2.98 × 10−20 cm2, respectively. The decay lifetime of 4G 5/2 energy level was measured to be 2.51 ms. All above results indicate the Sm:YAP crystal may be a potential candidate of reddish-orange laser pumped directly by the GaN/InGaN laser diode. • Sm:YAlO 3 crystal was grown by Cz method. • Polarized optical spectra of Sm:YAlO 3 crystal were investigated. • The transitions of 4G 5/2 → 6H 7/2 have the highest branching ratio value, which is suitable for reddish-orange laser. [ABSTRACT FROM AUTHOR]

Dy 3+ -doped YAlO 3 single crystal has been successfully grown by Czochralski technique. The spectroscopic parameters were determined by Judd-Ofelt theory based on the measured polarized absorption spectra. Dy:YAP crystal exhibits a yellow emission centered at 574 nm which can be used for pumping of the forbidden 1 S 0 - 3 P 0 ytterbium clock transition. The decay lifetime of the 4 F 9/2 level was measured to be 185 μs. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ce doped Al2O3−YAG eutectic has been successfully grown by the Czochralski method. [•] The eutectic has a higher segregation coefficient of Ce3+ than YAG single crystal. [•] Photoluminescence properties of Ce-doped Al2O3–YAG eutectic were investigated. [•] Variouswhitecolourscouldbeobtainedasrequired,byvaryingtheeutecticphosphorthickness. [•] The distinctive structure of eutectic made it have a better performance in LED than particle-dispersed system. [ABSTRACT FROM AUTHOR]

Tm3+- doped GdScO 3 single crystal was successfully grown by the edge-defined film-fed method (EFG) for the first time. The spectroscopic properties of the crystal were investigated at room temperature. The absorption cross section of Tm:GdScO 3 at 795 nm is 1.58 × 10−20 cm2. By applying the Judd–Ofelt approach, the intensity parameters Ω 2,4,6 , radiative transition rates, branching ratios and radiative lifetime were calculated. Tm:GdScO 3 exhibits strong emission at 1460 nm and 2300 nm with stimulated emission cross section of 1.8 × 10−21 cm2 and 2.7 × 10−21 cm2, respectively. The fluorescence lifetime of the 3H 4 level was measured to be 265 μs. All the results indicated that the Tm:GdScO 3 crystal is a potential laser material. • Tm:GdScO 3 crystal was successfully grown by the edge-defined film-fed method (EFG) for the first time. • The structure parameters of Tm:GdScO 3 crystal were investigated by XRD. • Spectral parameters and Judd-Ofelt parameters of Tm:GdScO 3 crystal were obtained and compared. [ABSTRACT FROM AUTHOR]