Figure - available from: Optics Letters
This content is subject to copyright. Terms and conditions apply.
Experimental setup. M1/M2, flat dichroic mirror; M3, flat silver mirror; M4, concave mirror ( RoC = 200 mm ); OC, flat output coupler; P , Brewster prism; and L1–L3, spherical lens ( f = 100 mm ).
Source publication
![Tuning range and beam profile [inset].](profile/Markus-Loeser/publication/231741929/figure/fig5/AS:11431281253677704@1718925286294/Tuning-range-and-beam-profile-inset_Q320.jpg)
Fabrication, spectroscopic properties, and laser performance of a Yb : SiO 2 multicomponent glass have been investigated in this paper. The glass system composed of SiO 2 , Al 2 O 3 , and La 2 O 3 excels in terms of a high thermal stress resistance compared to other laser glasses. The laser experiments were conducted with a 3.4 mm thick and 0.9 mol...
Similar publications
Er3+/Yb3+ co-doped tellurite glasses were fabricated. The thermal and optical properties of the tellurite glasses were studied. The presented glasses are potential candidates for the development of lasers and optical amplifiers.
CCD-based thermoreflectance imaging and finite element modeling are used to study the two-dimensional (2D) temperature profile of a junction-down broad-area diode laser facet subject to back-irradiance. By determining the temperature rise in the active region (ΔΤAR) at different diode laser optical powers, back-irradiance reflectance levels, and ba...
Microdisk lasers based on three InGaAsN/GaAs quantum wells with different types of surface passivation are fabricated and studied under optical pumping. Room temperature lasing at 1.3 μm in 7 μm in diameter microdisks with InGaAsN/GaAs QW is demonstrated. We evaluated the thermal resistance as 1 °C/mW.
Citations
... In addition, they provide high redox stability during thermal processing and large solubility capacity of various rare earth elements. This unique combination of properties makes SAL glasses promising materials for different applications, such as high nonlinearity fibers for supercontinuum generation [35], optical fiber switching, Raman amplifiers/lasers, compact fiber lasers with high rare earth concentration [36,40] and bulk laser media [41,42]. SAL glass is also of interest for microstructured optical fibers. ...
We report the use of the extrusion technique at highest temperatures to date (975 °C - 1000 °C) for the fabrication of suspended core fibers (SCFs) from glass with molar composition 65 SiO2-20 Al2O3-15 La2O3 (SAL65). Through adjusting die design and fabrication conditions, extruded preforms for fibers with two different core sizes (1.2 µm and 3.1 µm) were successfully produced. Cross-sectional microstructure and material loss of these fibers highlight the potential of the extrusion technique for fabrication of microstructured optical fibers from glasses with high softening temperature and thus high thermal and mechanical stability.
... Jaque et al. used a 2 mm thick Yb phosphate glass to demonstrate a laser slope as high as 53% and an output power of 0.8 W for a diode-pumped Yb 3þ laser operating at room temperature [14] . A broadband wavelength-tunable glass laser was obtained by Loeser et al. maintaining a tunable range of 80 nm and output power of 250 mW based on Yb:SiO 2 multicomponent glass [15] . Röser et al. enlarged the tuning range by using Yb-doped fused silica glass rods, producing a 100 nm tunable range with 350 mW maximum output power [16] . ...
The laser performance of a new Yb: germanophosphate (Yb:GP) glass is investigated. A maximum output power of 826 mW at 1063 nm is achieved with direct diode pumping at 976 nm. The wavelength is tuned from 1034.47 to 1070.83 nm, corresponding to a tuning range of 36.36 nm. Thermal lens effects are investigated to optimize the optical cavity.
... In addi- tion to the glasses listed in Table 6, a new type Yb 3+ - doped aluminosilicate glass was also reported. 50,56,57 This glass has a broader emission band and good thermo- mechanical properties. However, high melting temperature and difficulty in reducing hydroxyl content in glass are main obstacles for the fabrication of high-quality alumi- nosilicate laser glass. ...
This paper reviews the progress made on Nd3+, Er3+ and Yb3+ doped laser glasses at SIOM, China. Key properties of Nd: phosphate and Nd: fluorophosphate (FP) laser glasses are presented and compared with the commercial laser glasses from Hoya and Schott. Also reviewed are properties of four types of Er: phosphate glasses. The development of a continuous, large scale melting platform producing high quality Nd: phosphate laser glass at SIOM is briefly described. Our study on the Stark splitting of Yb3+: 2F7/2 level indicates that mixed glass formers can significantly improve the Stark splitting, resulting enhancement of lasing performance of Yb: phosphate glass. This article is protected by copyright. All rights reserved.
... New laser glasses based on multicomponent silicate glasses could be promising alternatives [6] with significantly improved thermomechanical properties based primarily on their low thermal expansion coefficient. In this work we present the results of a study on alumino-silicate glasses that was carried out during the ALASKA-project to find a potential replacement for the active medium in the POLARIS laser system. ...
We present a detailed investigation of different compositions of Yb3⁺-doped alumino-silicate glasses as promising materials for diode-pumped high-power laser applications at 1030 nm due to their beneficial thermo-mechanical properties. To generate comprehensive datasets for emission and absorption cross sections, the spectral properties of the materials were recorded at temperatures ranging from liquid nitrogen to room temperature. It was found that the newly developed materials offer higher emission cross sections at the center laser wavelength of 1030 nm than the so far used alternatives Yb:CaF2 and Yb:FP-glass. This results in a lower saturation fluence that offers the potential for higher laser extraction efficiency. Fluorescence lifetime quenching of first test samples was analyzed and attributed to the hydroxide (OH) concentration in the host material. Applying a sophisticated glass manufacturing process, OH concentrations could be lowered by up to two orders of magnitude, rising the lifetime and the quantum efficiency for samples doped with more than 6.10²⁰ Yb³⁺ -ions per cm³. First laser experiments showed a broad tuning range of about 60 nm, which is superior to Yb:CaF2 and Yb:FP-glass in the same setup. Furthermore, measurements of the laser induced damage threshold (LIDT) for different coating techniques on doped substrates revealed the appropriateness of the materials for short pulse high-energy laser amplification.
... Recently, different approaches have been investigated to overcome this limitation. An Yb-doped multicomponent glass composition based on fused silica has been developed, which could be produced directly out of a glass melt with large active volume and high optical quality [6]. Also, a new technique has been developed to produce Yb-doped fused silica bulk glass with scalable size [7], already showing an excellent performance in fiber laser applications [8][9][10] and even permitting the use as bulk gain material for diode-pumped high-energy lasers. ...
We report on the fabrication, optical properties and, to the first time to our knowledge, lasing characteristics of Yb-doped fused silica in bulk volume. The glass rods were manufactured by sintering of Yb-doped fused silica granulates and subsequent homogenization. Samples of various thicknesses containing doping levels of 0.27 mol% and 0.39 mol%, respectively, were investigated. The glass shows a high optical quality with refractive index variations in the 10 ppm range. We successfully demonstrated quasi-cw lasing with a maximum optical to optical efficiency of 60 % and slope efficiencies of about 70 % with respect to absorbed pump power for all samples. The laser cavity could be tuned in a wavelength range of 100 nm. The large amplification bandwidth of fused silica was verified by gain distribution measurements in a double-pass amplifier configuration.
... Therefore, Yb 3+ -laser is regarded as the most promising candidate for high energy, ultra-short-pulse laser that is needed in inertial confinement fusion experiments [2,3]. During the past decades, solid-state Yb 3+ -lasers have been witnessed great advancement [1,[4][5][6]. But the two-energy-level configuration of Yb 3+ results in two disadvantages for Yb 3+ -laser: high threshold and serious thermal load of the gain media for the reason that both the lower and ground laser manifolds belong to 2 F 7/2 level [7,8]. ...
Lasing properties have been investigated for Yb³⁺ doped glasses with similar emission cross sections (σemi) and lifetime while possessing different Stark levels. Narrow Stark splitting of Yb³⁺-phosphate glass is responsible for severe heat generation, narrow emission band and much smaller σemi at lasing wavelength, making Yb³⁺-phosphate glass unsuccessful to achieve laser output, whereas 1.166W cw laser was obtained in Yb³⁺-fluorophosphate (FP) glass with broader Stark splitting. Analysis on laser system levels reveals that under room temperature, Yb³⁺ laser is quasi-3.13-level in phosphate glass and quasi-3.36-level in FP glass. These demonstrations suggest that unless the Stark splitting is enlarged, conventional Yb³⁺-phosphate glass is not a good gain medium for bulk Yb³⁺-laser.
... Yb 3 -doped lasers have obtained significant achievements in civil and military applications [1][2][3][4][5]. More than 6 kw laser is demonstrated in a single Yb 3 -doped fiber [6], and a multi-10 TW Yb 3 -doped laser is also realized in glass [7]. ...
The room-temperature Stark splitting properties of Yb 3 + are practical and valuable for lasers because the working temperature of the gain media intensively increases with the laser output. In this Letter, the room-temperature Stark splitting properties of Yb 3 + in several popular laser glasses are contrastively studied. Yb 3 + -doped germanate (Ge), borate (B), silicate (Si), bismuthate (Bi), tellurite (Te), and fluorophosphate (FP) glasses exhibit large Stark splitting and tend to operate close to the quasi-four-level scheme, whereas phosphate (P) glass shows the weakest Stark splitting and tends to operate close to the quasi-three-level one. Due to the low thermal conductivity of the glass matrix, Yb 3 + -doped P glass suffers from serious thermal problems and is difficult to achieve high laser output. The Stark splitting is also used to estimate the crystal-field strength of glass hosts and local Yb 3 + ligand asymmetry degree. The results show that P glass shows weaker crystal-field effect and lower Yb 3 + ligand asymmetry than Ge, Si, and B glasses.
In this contribution, we analyze the effect of several preparation methods of Yb3+
doped alumino silicate glasses on their quantum efficiency by using photo-acoustic measurements in comparison to standard measurement methods including the determination via the fluorescence lifetime and an integrating sphere setup. The preparation methods focused on decreasing the OH concentration by means of fluorine-substitution and/or applying dry melting atmospheres, which led to an increase in the measured
fluorescence lifetime. However, it was found that the influence of these methods on radiative properties such as the measured
fluorescence lifetime alone does not per se give exact information about the actual quantum efficiency of the sample. The determination of the quantum efficiency by means of fluorescence lifetime shows inaccuracies when refractive index changing elements such as fluorine are incorporated into the glass. Since fluorine not only eliminates OH from the glass but also increases the “intrinsic” radiative fluorescence lifetime, which is needed to calculate the quantum efficiency, it is difficult to separate lifetime quenching from purely radiative effects. The approach used in this contribution offers a possibility to disentangle radiative from non-radiative properties which is not possible by using fluorescence lifetime measurements alone and allows an accurate determination of the quantum efficiency of a given sample. The comparative determination by an integrating sphere setup leads to the well-known problem of reabsorption which embodies itself in the measurement of too low quantum efficiencies, especially for samples with small quantum efficiencies.
The increasing fields of applications for modern optical fibers present great challenges to the material properties and the processing technology of fiber optics. This paper gives an overview of the capabilities and limitations of established vapor deposition fiber preform technologies, and discusses new techniques for improved and extended doping properties in fiber preparation. In addition, alternative fabrication technologies are discussed, such as a powder-based process (REPUSIL) and an optimized glass melting method to overcome the limits of conventional vapor deposition methods concerning the volume fabrication of rare earth (RE)-doped quartz and high silica glasses. The new preform technologies are complementary with respect to enhanced RE solubility, the adjustment of nonlinear fiber properties, and the possibility of hybrid fiber fabrication. The drawing technology is described based on the requirements of specialty fibers such as adjusted preform and fiber diameters, varying coating properties, and the microstructuring of fiber configurations as low as in the nanometer range.
