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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]

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]

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]

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]