We report on the real-space observation of resonant frequency splitting in a high-Q waveguide-coupled silicon-on-insulator microdisk resonator. Phase sensitive near-field analysis reveals the stationary nature of the two resonant states, and spectral investigations clearly show their orthogonality. These measurements emphasize the role of the coupling waveguide in this splitting phenomenon. The symmetry of the two stationary whispering gallery modes is clearly observed and is found to follow the axial symmetry of the waveguide-coupled microdisk as it has been reported by earlier theoretical predictions.
© 2010 Optical Society of America
Original Manuscript: June 29, 2010
Revised Manuscript: August 24, 2010
Manuscript Accepted: August 27, 2010
Published: September 20, 2010
Sylvain Blaize, Felice Gesuele, Ilan Stefanon, Aurélien Bruyant, Gilles Lérondel, Pascal Royer, Bruno Martin, Alain Morand, Pierre Benech, and Jean-Marc Fedeli, "Real-space observation of spectral degeneracy breaking in a waveguide-coupled disk microresonator," Opt. Lett. 35, 3168-3170 (2010)