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arXiv · 1711.03468

Suspended silicon waveguides for long-wave infrared wavelengths

J. Soler Penadés·A. Sánchez-Postigo·M. Nedeljkovic·A. Ortega-Moñux·J. G. Wangüemert-Pérez·Y. Xu·R. Halir·Z. Qu·A. Z. Khokhar·A. Osman·W. Cao·C. G. Littlejohns·P. Cheben·I. Molina-Fernández·G. Z. Mashanovich
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Abstract

In this paper we report suspended silicon waveguides operating at a wavelength of 7.67 mm with a propagation loss of 3.1 ? 0.3 dB/cm. To our knowledge this is the first demonstration of low loss silicon waveguides at such a long wavelength, with loss comparable to other platforms that use more exotic materials. The suspended Si waveguide core is supported by a subwavelength grating that provides lateral optical confinement, while also allowing access to the buried oxide layer so that it can be wet etched using hydrofluoric acid. We also demonstrate low loss waveguide bends and s-bends.

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J. Soler Penadés, A. Sánchez-Postigo, M. Nedeljkovic, A. Ortega-Moñux, J. G. Wangüemert-Pérez, Y. Xu, R. Halir, Z. Qu, A. Z. Khokhar, A. Osman, W. Cao, C. G. Littlejohns, P. Cheben, I. Molina-Fernández, G. Z. Mashanovich. 2017-11-09. Suspended silicon waveguides for long-wave infrared wavelengths. https://arxiv.org/abs/1711.03468

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