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arXiv · 1102.2370

Monolithic whispering-gallery mode resonators with vertically coupled integrated bus waveguides

Mher Ghulinyan·Romain Guider·Georg Pucker·Lorenzo Pavesi
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Abstract

We report on the realization and optical characterization of a CMOS-compatible silicon-based microresonator/waveguide coupled system, fully integrated on a silicon chip. The device uses a vertical coupling scheme between the resonator and a buried strip waveguide. We demonstrate that its high optical quality follows from the accurate planarization of the waveguide topography. More importantly, we demonstrate a wafer-scale mass fabrication of freestanding planar resonators suspended in air and coupled to the integrated bus waveguides. A nanometer control of the coupling distances allows for a precise and selective excitation of different mode families of the resonator. This opens the door for the realization of stable all-integrated complex resonator systems for optomechanical and metrological applications, with the potential to substitute the nowadays intensive use of complicated fiber-taper coupling schemes.

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Mher Ghulinyan, Romain Guider, Georg Pucker, Lorenzo Pavesi. 2011-02-11. Monolithic whispering-gallery mode resonators with vertically coupled integrated bus waveguides. https://doi.org/10.1109/lpt.2011.2157487

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