Dimitri Geskus

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A reliable and reproducible deposition process for the fabrication of Al O waveguides with losses as low as 0.1 dB/cm has been developed. The thin films are grown at nm deposition rate and exhibit excellent thickness uniformity within 1% over 50 50 mm area and no detectable OH incorporation. For applications of the Al O films in compact, integrated optical(More)
Epitaxially grown, 2.4-microm-thin layers of KY(WO(4))(2):Gd(3+), Lu(3+), Yb(3+), which exhibit a high refractive index contrast with respect to the undoped KY(WO(4))(2) substrate, have been microstructured by Ar beam milling, providing 1.4-microm-deep ridge channel waveguides of 2 to 7 microm width, and overgrown by an undoped KY(WO(4))(2) layer. Channel(More)
By exploiting large transition cross-sections, high dopant concentration, and strong light confinement, a gain of 950 dB/cm is demonstrated in a large-refractive-index-contrast KGd<inf>x</inf>Lu<inf>1&#x2212;x</inf>(WO<inf>4</inf>)<inf>2</inf>:Yb<sup>3&#x002B;</sup> channel waveguide, representing a two-orders-of-magnitude improvement over previous results(More)
A reliable and reproducible deposition process for the fabrication of Al<sub>2</sub>O<sub>3</sub> waveguides with losses as low as 0.1 dB/cm has been developed. The thin films are grown at ~ 5 nm/min deposition rate and exhibit excellent thickness uniformity within 1% over 50times50 mm<sup>2</sup> area and no detectable OH<sup>-</sup> incorporation. For(More)
Channel waveguides based on a polymer, 6-fluorinated-dianhydride/epoxy, which is actively doped with a Nd complex, Nd(thenoyltrifluoroacetone)(3) 1,10-phenanthroline, are fabricated by a simple and reproducible procedure, spin coating a photodefinable cladding polymer onto a thermally oxidized silicon wafer, photopatterning, backfilling with the active core(More)
ISBN 978-3-00-024191-8 27th 30th September 2009, Capri, Italy Highly efficient Gd, Lu co-doped KY(WO4)2:Yb3+ planar waveguide laser Dimitri Geskus, Shanmugam Aravazhi, Edward Bernhardi, Christos Grivas, Kerstin Wörhoff, Markus Pollnau University of Twente, MESA+ Institute for Nanotechnology, Integrated Optical MicroSystems Group, 7500 AE Enschede,(More)
Channel waveguide lasers operating at 981 nm are demonstrated in KY(1-x-y)Gd(x)Lu(y)(WO4)2:Yb3+ waveguides grown by liquid phase epitaxy onto undoped KY(WO4)2 substrates and microstructured by Ar+ beam etching. Under pumping at 934 nm of samples with different waveguide geometry and outcoupling degree, a record-high slope efficiency of 76% versus absorbed(More)
In KGd(1-x)Lu(x)(WO(4))(2):Yb(3+) channel waveguides grown onto KY(WO(4))(2) substrates by liquid phase epitaxy and microstructured by Ar+ beam etching, we produced 418 mW of continuous-wave output power at 1023 nm with a slope efficiency of 71% and a threshold of 40 mW of launched pump power at 981 nm. The degree of output coupling was 70%. By grating(More)