The spectral responses of series-coupled racetrack resonators exhibiting the Vernier effect have many attractive features as compared to the spectral responses of identical series-coupled racetrack resonators, such as free spectral range (FSR) extension and enhanced wavelength tunability. Here we present experimental results of a thermally tunable quadruple series-coupled silicon racetrack resonator exhibiting the Vernier effect. We thermally tune two of the four racetrack resonators to enable discrete switching of the major peak by 15.54 nm. Also, our device has an interstitial peak suppression of 35.4 dB, a 3 dB bandwidth of 0.45 nm, and an extended FSR of 37.66 nm.
© 2013 Optical Society of America
Original Manuscript: March 18, 2013
Revised Manuscript: May 22, 2013
Manuscript Accepted: May 31, 2013
Published: July 9, 2013
Robert Boeck, Lukas Chrostowski, and Nicolas A. F. Jaeger, "Thermally tunable quadruple Vernier racetrack resonators," Opt. Lett. 38, 2440-2442 (2013)