Title :
Tunable narrow linewidth all-buried heterostructure ring resonator filters using vernier effects
Author :
Choi, Sang Jun ; Peng, Zhen ; Yang, Qi ; Sang Jun Choi ; Dapkus, P.Daniel
Author_Institution :
Dept. of Electr. Eng.-Electrophys., Univ. of Southern California, Los Angeles, CA, USA
Abstract :
Channel configurable optical filters are realized by using buried heterostructure semiconductor ring resonators. Two rings having slightly different radii are laterally coupled to bus waveguides in a cascaded manner, which affords free spectral range (FSR) expansion and channel configuration by Vernier effects. The effective FSR and spectral linewidth at resonance measured from a drop port are 10.2 and 0.017 nm, respectively, that corresponds to a finesse (F) of 600. By shifting the resonant wavelength of one of the resonators with free carrier injection, we demonstrate digital tuning filters where a distinct channel isolation of 15-20 dB is achieved with 0.68-nm spectral spacing.
Keywords :
digital filters; integrated optics; optical filters; optical resonators; optical tuning; optical waveguides; semiconductor devices; spectral line breadth; Vernier effect; all-buried heterostructure filters; bus waveguides; channel configurable optical filters; digital tuning filters; distinct channel isolation; free carrier injection; free spectral range expansion; narrow linewidth filters; photonic integrated circuits; resonant wavelength shift; ring resonator filters; semiconductor ring resonators; spectral linewidth; tunable filters; Optical filters; Optical losses; Optical resonators; Optical ring resonators; Optical scattering; Optical waveguides; Particle scattering; Resonance; Resonator filters; Semiconductor waveguides; Buried heterostructure (BH); Vernier effects; channel configurable filters; finesse; free carrier injection (FCI); free spectral range (FSR); ring resonators; spectral linewidth;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2004.838626