Search

Erbium (Er)- and Ytterbium (Yb)-codoped monoclinic KLu(WO4) 2 single crystals were grown by top seeded solution growth-slow cooling method for several different doping concentrations. Growth parameters have been optimized to obtain macrodefect-free single crystals. Er energy levels involved in the 4I13/2 → 4I 15/2 were determined by 6 K polarized optical absorption. The maximum emission cross section for this electronic transition has been evaluated, being 2.85 × 10-20 cm2 for E||Nm at 1535 nm. Laser oscillation in the 1.5 μm range was obtained by pumping the Yb ion at 980 nm and sensitizing Er. The maximum output power achieved was 152 mW, with 1.2% slope efficiency., QC 20141020

High quality Er:Yb:KLu(WO4)2have been grown using TSSG method and spectroscopically investigated . The laser performance is compared with that in Er:Yb:KY(WO4)2. Role of upconversion processes and optimum doping concentrations have been estimated., QC 20140925

We report a 236 nm light source with 20 mW of average power based on critically phase-matched second-harmonic generation in a beta-barium borate crystal at room temperature. The fundamental light source was a passively Q-switched 946 nm Nd: YAG laser tunable from 10-38 kHz and with a pulse length of 16 ns. In the generation of 473 nm light, periodically poled KTP and BiBO was compared in terms of conversion efficiency and stability., Uppdaterad från submitted till published: 20100903QC 20100903

Quasi-steady state SRS with 1.7 ps pulses is investigated in tetragonal Nay(WO4)(2) and NaLa(WO4)(2) crystals in the regimes of collinear and noncollinear SRS-assisted four-wave-mixing. Single-pass conversion efficiency of 31% is reported., QC 20110307

The fluorescence dynamics in Er3+ and Yb3+ doped KGd(WO4)(2) and KY(WO4)(2) has been investigated. Lifetimes have been measured for the Yb(F-2(5/2)), Er(I-4(13/2)), and Er(S-4(3/2)) levels around 1, 1.5, and 0.55 mu m, respectively. The Yb(F-2(5/2)) lifetimes show a decreasing trend toward the limiting Er(I-4(11/2)) lifetime with increasing Er-to-Yb concentration ratio, whereas the Er(I-4(13/2)) lifetimes are mostly unaffected by the doping concentrations. A rate equation analysis has been performed to explain the observed behavior and gain is calculated for a continuous-wave laser at 1.53 mu m to find the optimum doping concentrations for high gain., QC 20100713. Uppdaterad från Accepted till Published 20100713.

A comparative, experimental study of the high-power diode-pumped laser performance and thermal lensing properties between standard b-cut Yb:KGW and Yb:KGW cut along an athermal direction is presented. The results show that thermal lens properties in both the b-cut and the athermal direction-cut crystals are determined by anisotropic thermal expansion in Yb:KGW. Thermal gradients due to the pump beam cause thermal lensing even in the athermal direction-cut geometry. The thermal lens is much weaker and less astigmatic in the athermal direction-cut crystal, for the same absorbed power. These properties allow generation of better-quality laser beams with the athermal direction-cut crystal as compared to the b-cut crystal., QC 20100714

We present theoretical and experimental investigations on ground-state direct pumping at 869 nm into the emitting level F-4(3/2) of end-pumped quasi-three-level Nd:YAG lasers operating at 946 nm. We have demonstrated, what we believe is for the first time, a Nd:YAG laser at 946 nm directly pumped by diodes and obtained 1.6 W of output power., QC 20100901. Uppdaterad från Submitted till Published 20100901.

The laser performance of Yb:KGW under end-pumping with high-power diode bars has been investigated. In one configuration, the pump is delivered through an optical fiber yielding a symmetric but unpolarized pump spot. In the second configuration, the pump is delivered through an optical lens system yielding a polarized but asymmetric pump spot. Both configurations resulted in a maximum optical to optical efficiency of 47% and a maximum power of 12.4 W has been generated with the fiber coupled pump source. The output power was limited by crystal fracture, which occurred at an estimated temperature gradient of 1.2 x 10(5) K/m. Thermal lensing and laser tuning characteristics are also investigated., QC 20100714. Uppdaterad från Accepted till Published 20100714.

The generation of 12.4W of output power with optical-to-optical conversion efficiency of 47% and slope efficiency of 74% is demonstrated in Yb:KGW laser end-pumped with high-power diode bars. Thermal-lensing and laser tuning has been investigated., QC 20141111

A comparative, experimental study between b-cut Yb:KGW and Yb:KGW cut along a proposed athermal direction is presented. The athermal direction gives a significantly weaker thermal lens, lower astigmatism and higher beam quality under lasing conditions., QC 20150414

We have demonstrated, what we believe is for the first time, direct diode-pumping at 869 rim into the emitting level of a quasi-three-level Nd:YAG laser operating at 946 nm., QC 20111014

QC 20141201

A high-power Q-switched Nd:YAG/Cr:YAG laser mounted in a silicon microbench is presented. It reaches an average output power well above 2 W and the pulse width is in the order of 1.4 ns. The use of microstructure silicon carriers provides efficient thermal control, compact integration and alignment of active and passive optical components., QC 20100901

Efficient room-temperature operation of F-4(3/2) --> I-4(9/2) transitions in diode-end-pumped Nd:YAG lasers at 946 nm and 938.5 nm is reported. 7.0-W continuous-wave output power at 946 nm and 3.9 W at 93 8.5 nm have been obtained. An analytical model has been developed for the quasi-three-level laser including the influence of energy-transfer upconversion. Frequency doubling of these transitions in periodically poled KTP generated blue light at 473 nm and 469 nm. Both single-pass extra-cavity as well as intracavity schemes have been investigated., QC 20100901

A continuation of the previously introduced microstructured silicon carrier concept for diode-pumped solid-state lasers is presented, using novel heat-conducting polymers as a carrier. The most prominent features of the silicon carrier concept are maintained, adding to the mass production possibilities of the inexpensive polymers. The first experiments, using a continuous wave Nd:YAG microchip laser, have given an output power of 2 W at 1064 nm, showing the potential of this new approach., QC 20100901

Efficient operation of a diode-pumped Nd: YAG laser at 938.5 nm is reported. A continuous wave output power of 3.9 W is obtained. Single-pass frequency doubling in periodically poled KTP delivered a power of 88 mW at 469 nm. By intracavity frequency doubling an output of 200 mW in the blue region is achieved., QC 20100901