Analysis of the Spectrum Characteristics of a Super Linear Optical Modulator

摘要

We demonstrate the superior RF spectrum characteristics of an ultra-linear modulator. This modulator exhibits excellent linearity (Spurious Free Dynamic Range, SFDR ~ 133 dB at lHz bandwidth), wider linearization bandwidth (an order of magnitude wider), and flatter RF modulation frequency dependence characteristics (linearized 3dB bandwidth ~ 20% of central RF frequency) when compared with Resonator-Assisted Mach Zehnder (RAMZ) modulators. The modulator is based on a traveling-wave electrode design, in which a phase modulator (PM) is on the upper arm of a Mach Zehnder (MZ) interferometer and a ring resonator (RR) is located on the lower arm. This modulator design is also shown to have flexible control of the power split ratio of an RF input to both the PM and the RR, in addition to the RF phase bias between the RR and PM -which enables better manufacturing tolerance.