We report on the design and fabrication of straight and S-curved waveguides in neodymium-doped yttrium aluminate (Nd:YAP) crystal by using direct femtosecond laser writing. These S-curved channel waveguides are based on the hexagonal optical-lattice-like and depressed cladding geometry. For each type waveguide, S-curves with three lateral offsets of 50 μm, 100 μm, and 150 μm are implemented. These waveguides are with good guiding properties and low bending losses. With S-curved waveguide as laser cavity, dual-wavelength, 31.6 GHz waveguide laser operating at 1064 nm and 1079 nm have been demonstrated based on MoS2 as a saturable absorber. This work paves the way to develop new on-chip ultrafast laser sources based on femtosecond laser inscribed S-curved waveguides.

中文翻译：

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Nd:YAP 晶体中飞秒激光写入的 S 型弯曲波导：制造和多千兆赫激光

我们报告了使用直接飞秒激光写入在掺钕铝酸钇 (Nd:YAP) 晶体中设计和制造直线和 S 曲线波导。这些 S 形弯曲通道波导基于六边形光学晶格和凹陷包层几何形状。对于每种类型的波导，实现了具有 50 μm、100 μm 和 150 μm 三个横向偏移的 S 曲线。这些波导具有良好的引导特性和低弯曲损耗。使用 S 型弯曲波导作为激光腔，已经证明了基于 MoS2 作为可饱和吸收体的双波长 31.6 GHz 波导激光器，工作在 1064 nm 和 1079 nm。这项工作为开发基于飞秒激光刻划 S 型弯曲波导的新型片上超快激光源铺平了道路。