High power laser operation with crystal fibers

250 W single-crystal fiber Yb:YAG laser

“…As reported in [4], the thermal contact was responsible of 80% of the total temperature difference between the crystal center and the mount in a single-crystal fiber surrounded by thermal grease in a nonoptimized mount. The Laboratoire Charles Fabry and Fibercryst have worked together to develop an excellent metallic contact in the single-crystal fiber TARANIS modules [6].…”

“…This high value can be explained by two factors. Firstly, due to the lower brightness of the pump beam, no soft aperture mode filtering occurs, as observed previously [4]. Secondly, the cavity design was not fully optimized and we believe that the use of a larger resonant fundamental mode would result in an improvement of the beam quality.…”

“…Up to now, a maximum of 65 W of output power in continuous-wave has been demonstrated using an Yb: YAG single-crystal fiber at a pump power of 200 W at 940 nm [4]. This concept has started to reveal its potential as a femtosecond amplifier with a combination of high gain (30) and significant output power (12 W) in a very simple double-pass configuration [5].…”

34 W continuous wave Nd:YAG single crystal fiber laser emitting at 946 nm

“…As opposed to the planar waveguide, the signal beam is in free propagation in the single crystal fiber, and its profile is defined by a cavity with two external mirrors for mode filtering. The concept of single crystal fiber has already been used successfully for a quasi-three level laser: the Yb:YAG with an output power of 50 W at 1030 nm [13]. Consequently, this laser crystal geometry seems to have a good potential for the development of high power quasi-three level Nd:YAG lasers at 946 nm.…”

Direct amplification of ultrashort pulses in µ-pulling down Yb:YAG single crystal fibers

“…Fortunately, the micro-pulling-down crystal growth is now a mature technique remarkably suited for the production of long (up to 1 m) and thin (down to 300 μm diameter) Yb:YAG SCFs with laser optical quality [5]. Interesting laser performances have been reported in cw and Q-switched Yb:YAG SCF oscillators [6].…”