Share Email Print

Proceedings Paper

New spherical optical cavities with non-degenerated whispering gallery modes
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

New spherical resonators with internal defects are introduced to show anomalous whispering gallery modes (WGMs). The defect induces a symmetry breaking spherical cavity and splits the WGMs. A couple of defects, a hollow sphere (bubble), and a hollow ring, have been studied. The hollow sphere was fabricated and the splitting of WGM was observed. In this paper, this "non-degenerated WGMs (non-DWGMs) resonance" in a microsphere with hollow defect structure is reviewed based on our research. The resonance of WGMs in a sphere is identified by three integer parameters: the angular mode number, l, azimuthal mode number m, and radial mode number, n. The placement of the defect such as a hollow ring or single bubble is shown to break symmetry and resolve the degeneracy concerning m. This induces a variety of resonant wavelengths of the spherical cavity. A couple of simulations using the eigenmode and transient analyses propose how the placed defects affect the WGM resonance in the spherical cavity. For the sphere with a single bubble defect, the experimentally observed resonances in Nd-doped tellurite glass microsphere with a single bubble are clarified to be due to the splitting of resonance modes, i.e., the existence of "non-DWGMs" in the sphere. The defect bubble plays a role of opening the optically wide gate to introduce excitation light for Nd3+ pumping using non-DWGMs in the sphere efficiently.

Paper Details

Date Published: 20 February 2017
PDF: 9 pages
Proc. SPIE 10090, Laser Resonators, Microresonators, and Beam Control XIX, 100901F (20 February 2017); doi: 10.1117/12.2251599
Show Author Affiliations
Tsutaru Kumagai, Tokyo Institute of Technology (Japan)
Giuseppe Palma, Politecnico di Bari (Italy)
Francesco Prudenzano, Politecnico di Bari (Italy)
Tetsuo Kishi, Tokyo Institute of Technology (Japan)
Tetsuji Yano, Tokyo Institute of Technology (Japan)

Published in SPIE Proceedings Vol. 10090:
Laser Resonators, Microresonators, and Beam Control XIX
Alexis V. Kudryashov; Alan H. Paxton; Vladimir S. Ilchenko, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?