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arXiv · 1901.01496

Excitation of whispering gallery modes with a "point-and-play", fiber-based, optical nano-antenna

Jonathan M. Ward·Fuchuan Lei·Stephy Vincent·Pooja Gupta·Samir K Mondal·Jochen Fick·Síle Nic Chormaic
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Abstract

We demonstrate the excitation and detection of whispering gallery modes in optical microresonators using a "point-and-play", fiber-based, optical nano-antenna. The coupling mechanism is based on cavity-enhanced Rayleigh scattering. Collected spectra exhibit Lorentzian dips, Fano shapes, or Lorentzian peaks, with a coupling efficiency around 13\%. The spectra are characterized by the coupling gap, polarization, and fiber tip position. The coupling method is simple, low-cost and, most importantly, the \textit{Q}-factor can be maintained at $10^8$ over a wide coupling range, thereby making it suitable for metrology, sensing, or cavity quantum electrodynamics (cQED) experiments.

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Jonathan M. Ward, Fuchuan Lei, Stephy Vincent, Pooja Gupta, Samir K Mondal, Jochen Fick, Síle Nic Chormaic. 2019-06-24. Excitation of whispering gallery modes with a "point-and-play", fiber-based, optical nano-antenna. https://doi.org/10.1364/ol.44.003386

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