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arXiv · 1302.2658

Low bend loss waveguides enable compact, efficient 3D photonic chips

Alexander Arriola·Simon Gross·Nemanja Jovanovic·Ned Charles·Peter G. Tuthill·Santiago M. Olaizola·Alexander Fuerbach·Michael J. Withford
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Abstract

We present a novel method to fabricate low bend loss femtosecond-laser written waveguides that exploits the differential thermal stabilities of laser induced refractive index modifications. The technique consists of a two-step process; the first involves fabricating large multimode waveguides, while the second step consists of a thermal post-annealing process, which erases the outer ring of the refractive index profile, enabling single mode operation in the C-band. By using this procedure we report waveguides with sharp bends (down to 16.6 mm radius) and high (80%) normalized throughputs. This procedure was used to fabricate an efficient 3D, photonic device known as a pupil-remapper with negligible bend losses for the first time. The process will also allow for complex chips, based on 10's - 100's of waveguides to be realized in a compact foot print with short fabrication times.

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Alexander Arriola, Simon Gross, Nemanja Jovanovic, Ned Charles, Peter G. Tuthill, Santiago M. Olaizola, Alexander Fuerbach, Michael J. Withford. 2013-02-11. Low bend loss waveguides enable compact, efficient 3D photonic chips. https://doi.org/10.1364/oe.21.002978

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