Progress on micro-structured KY(WO₄)₂ waveguides for optically active devices

The optical properties of rare-earth-ion (RE) doped $KY{(WO_4)}_2$ $(KYW)$ form an excellent basis for the realization of optically active devices such as lasers and amplifiers. External-cavity laser experiments on KYW:Yb planar waveguides confirmed these predictions by high slope efficiencies up to 80%. In-house equipment enables the epitaxial growth of KYW:RE layers and their optical characterization. Combined with micro-structuring of KYW:RE layers using novel reactive-ion-etching methods (to an etch depth of ~390 nm) and use of simulation software (Field Designer), this will lead to novel on-chip integrated lasers and amplifiers and a profound understanding of the physics and optimization of these devices.