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arXiv · 1806.00140

Brillouin spectroscopy of a hybrid silicon-chalcogenide waveguide with geometrical variations

Atiyeh Zarifi·Birgit Stiller·Moritz Merklein·Yang Liu·Blair Morrison·Alvaro Casas-Bedoya·Gang Ren·Thach G. Nguyen·Khu Vu·Duk-Yong Choi·Arnan Mitchell·Stephen J. Madden·Benjamin J. Eggleton
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Abstract

Recent advances in design and fabrication of photonic-phononic waveguides have enabled stimulated Brillouin scattering (SBS) in silicon-based platforms, such as under-etched silicon waveguides and hybrid waveguides. Due to the sophisticated design and more importantly high sensitivity of the Brillouin resonances to geometrical variations in micro- and nano-scale structures, it is necessary to have access to the localized opto-acoustic response along those waveguides to monitor their uniformity and maximize their interaction strength. In this work, we design and fabricate photonic-phononic waveguides with a deliberate width variation on a hybrid silicon-chalcogenide photonic chip and confirm the effect of the geometrical variation on the localized Brillouin response using a distributed Brillouin measurement.

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Atiyeh Zarifi, Birgit Stiller, Moritz Merklein, Yang Liu, Blair Morrison, Alvaro Casas-Bedoya, Gang Ren, Thach G. Nguyen, Khu Vu, Duk-Yong Choi, Arnan Mitchell, Stephen J. Madden, Benjamin J. Eggleton. 2018-05-31. Brillouin spectroscopy of a hybrid silicon-chalcogenide waveguide with geometrical variations. https://doi.org/10.1364/ol.43.003493

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