Diode-end-pumped 12 W Yb:Y_2O_3 planar waveguide laser

Abstract

Fabrication, characterization and laser performance of a Watt-level ytterbium-doped yttria waveguide laser is presented. The waveguide was grown onto a YAG substrate by pulsed laser deposition and features a 6 µm thick ytterbium-doped yttria layer sandwiched between two 3 µm undoped yttria layers. The laser deposited film was characterized by X-ray diffraction, showing a high degree of crystallinity and analyzed spectroscopically, showing performance indistinguishable from previously reported bulk material. When pumped with 8.5 W from a broad area diode laser the waveguide laser produces 1.2 W of output at 1030 nm.

Mid-infrared laser emission from Cr:ZnS channel waveguide fabricated by femtosecond laser helical writing

“…Channel waveguides have been developed in Nd:YAG ceramics and crystals, Nd:YVO 4 , Yb:YAG, Cr:ZnSe, and Cr:ZnS 1 18 31 32 33 34 35 , which provide the potential for lower emission thresholds and maintain high gains over longer propagation distances. Efficient laser emission was reported using these waveguides when pumped with tunable Ti-sapphire lasers or diode lasers 27 36 37 .…”

Particulate reduction in PLD-grown crystalline films via bi-directional target irradiation

“…Table 1 shows the range in propagation loss for these 3 films grown with bi-directional ablation, compared to all our previously measured samples grown with the uni-directional approach. The results demonstrate a clear connection between reduced number density of surface particulates and lower propagation loss, which is approaching loss-values achieved via other fabrication methods and is a major improvement with respect to previous PLD-grown waveguides [5,6]. This shows great promise for high-efficiency, PLD-grown amplifier devices, suited to high-peakpower and ultra-short laser pulses.…”

“…PLD has been demonstrated as a viable technique for the growth of single-crystal planar waveguide devices fabricated from a range of materials, including doped sapphire (Al 2 O 3 ) [3,4], sesquioxides [5,6] and in particular, garnets [7]. This can be a relatively fast deposition process, and to date, growth rates of 25-µm per hour have been achieved on 1-cm 2 samples [8].…”

Lasing of Nd3+ in sapphire

“…Applying ion beam etching or diamond dicing, ridge waveguides could be prepared from the planar samples to benefit from the advantages of two dimensional confinement such as a better overlap of pump and laser mode . Thicker films could enable power scaling of Nd:sapphire in thin disk configuration or by direct end pumping of planar waveguides with diode bars . As laser action of rare‐earth‐doped sapphire is now proven it is worthwhile to investigate other crystal growth techniques apart from thermal equilibrium such as micro‐pulling‐down at high growth rates .…”

“…However, up to now no reports on lasing obtained from RE:sapphire can be found. Nevertheless PLD has proven to be a versatile method to grow thin films capable for laser oscillation in waveguide configuration in well‐established materials such as garnets as well as emerging materials like sesquioxides .…”