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arXiv · 1708.02873

Enhancement of bulk second-harmonic generation from silicon nitride films by material composition

K. Koskinen·R. Czaplicki·A. Slablab·T. Ning·A. Hermans·B. Kuyken·V. Mittal·G. S. Murugan·T. Niemi·R. Baets·M. Kaurenen
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Abstract

We present a comprehensive tensorial characterization of second-harmonic generation from silicon nitride films with varying composition. The samples were fabricated using plasma-enhanced chemical vapor deposition, and the material composition was varied by the reactive gas mixture in the process. We found a six-fold enhancement between the lowest and highest second-order susceptibility, with the highest value of approximately 5 pm/V from the most silicon-rich sample. Moreover, the optical losses were found to be sufficiently small (below 6 dB/cm) for applications. The tensorial results show that all samples retain in-plane isotropy independent of silicon content, highlighting the controllability of the fabrication process.

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K. Koskinen, R. Czaplicki, A. Slablab, T. Ning, A. Hermans, B. Kuyken, V. Mittal, G. S. Murugan, T. Niemi, R. Baets, M. Kaurenen. 2017-08-09. Enhancement of bulk second-harmonic generation from silicon nitride films by material composition. https://doi.org/10.1364/ol.42.005030

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