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arXiv · 1505.03628

High-Q coupled resonances on a PhC waveguide using a tapered nanofiber with high coupling efficiency

Tomohiro Tetsumoto·Yuta Ooka·Tanabe Takasumi
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Abstract

We experimentally demonstrate high-Q cavity formation at an arbitrary position on a silicon photonic crystal waveguide by bringing a tapered nanofiber into contact with the surface of the slab. An ultrahigh Q of 5.1 x 10^5 is obtained with a coupling efficiency of 39%, whose resonant wavelength can be finely tuned by 27 pm by adjusting the contact length of the nanofiber. We also demonstrate an extremely high coupling efficiency of 99.6% with a loaded Q of 6.1 x 10^3. In addition, we show that we can obtain an all-pass filter type coupled resonator system, which has the potential to be used for slow light generation.

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Tomohiro Tetsumoto, Yuta Ooka, Tanabe Takasumi. 2015-05-14. High-Q coupled resonances on a PhC waveguide using a tapered nanofiber with high coupling efficiency. https://doi.org/10.1364/oe.23.016256

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