Article

Double waveguide couplers produced by simultaneous femtosecond writing. Opt. Express 17, 3555-3563

Institute of Quantum Optics, Leibniz UniversitäHannover, Welfengarten 1, D-30167 Hannover, Germany.
Optics Express (Impact Factor: 3.49). 04/2009; 17(5):3555-63. DOI: 10.1364/OE.17.003555
Source: PubMed

ABSTRACT We report on a novel method to create waveguide coupler devices in fused silica by combining the technique of beam shaping with femtosecond laser writing. The method is based on a programmable phase modulator and a dynamic variation of the phase-pattern during the writing process. The major advantage is the possibility to create complex devices in a single sweep by simultaneously writing two or more waveguides with changing separation. The guiding properties and the coupling behavior between the waveguides are investigated.

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    • "We use this technique for the fabrication of complex integrated optical devices in a single sweep. In particular, we demonstrate multiple parallel waveguides and directional couplers [1]. The writing of one waveguide after the other may result in different optical properties in particular when the distance is small, since the second waveguide is partially fabricated on an already modified region. "
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