Similarities between birefringent Gires-Tournois interferometer and double ring assisted Mach- Zehnder electrooptic modulator

Recently, Gires-Tournois´s interferometer (GTI) relying on electrooptic materials have been attracting great interest because they may enable high linear dynamic range optical modulators. Therefore GTI´s may play a major role on the subject of signal processing in the field of microwave photonics. This paper addresses the modeling of a novel birefringent GTI modulator set - up as a double ring assisted Mach-Zehnder modulator (RAMZI). The modeling takes into account the front surface mirror reflectance and reveals that GTI based modulators may yield a dynamic range as high as that achieved with RAMZI, with requires a rather more complex fabrication technology. Results of numerical simulations obtained with a GTI configuration which relies on lithium niobate (LiNbO₃) and enables a push-pull operation with a single voltage source are presented.