Abstract

We demonstrate an ultra-narrow-band optical filter based on a hybrid-microsphere consisting of a coated SiO₂ microsphere. As compared to the SiO₂ microsphere, the hybrid-microsphere produces a quality factor of >10⁸, a transmission spectrum bandwidth of <1 pm, and an increased side-mode suppression ratio. The microsphere surface roughness and whispering gallery mode (WGM) transmission spectra are measured experimentally. A 0.01 nm bandwidth, single-wavelength fiber laser output is achieved with a tunable wavelength, using the SiO₂ microsphere as the mode selector. The optical field distribution and WGM transmission spectrum of the hybrid-microsphere with different coating parameters are theoretically investigated by the finite-difference time-domain method.

© 2016 Chinese Laser Press

Tuning whispering gallery modes in optical microspheres with chemical etching

Ian M. White, Niranjan M. Hanumegowda, Hesam Oveys, and Xudong Fan
Opt. Express 13(26) 10754-10759 (2005)

Whispering gallery mode structure in polymer-coated lasing microspheres

K. Gardner, Y. Zhi, L. Tan, S. Lane, Y.-F. Xiao, and A. Meldrum
J. Opt. Soc. Am. B 34(10) 2140-2146 (2017)

Whispering gallery mode microsphere resonator integrated inside a microstructured optical fiber

Kyriaki Kosma, Gianluigi Zito, Kay Schuster, and Stavros Pissadakis
Opt. Lett. 38(8) 1301-1303 (2013)

Surface-enhanced Raman scattering on dielectric microspheres with whispering gallery mode resonance

Steven H. Huang, Xuefeng Jiang, Bo Peng, Corey Janisch, Alexander Cocking, Şahin Kaya Özdemir, Zhiwen Liu, and Lan Yang
Photon. Res. 6(5) 346-356 (2018)

Whispering gallery modes in hybrid Au-ZnO microsphere resonators: experimental and theoretical investigations

Trong Huynh-Buu Ngo and Yia-Chung Chang
Opt. Mater. Express 7(8) 2962-2967 (2017)