Design and improvement of InP-based traveling wave Mach-Zehnder modulator for monolithic integrated with V-cavity laser

We propose a simple and effective model to properly design the monolithically integrated tunable optical transmitter based on the traveling wave Mach-Zehnder modulator (TW-MZM) and V-cavity laser (VCL). Firstly, the integrated structure of TW-MZM and VCL is presented. Then we put forward a TW-MZM model to design and improve the performance of the electro-optic (EO) modulation bandwidth of the optical transmitter. By changing the structural parameters of the optical waveguide and the traveling wave electrodes, we reduce the microwave transmission loss from 3 mm-1 to 0.6 mm-1 at 20 GHz and thus increase the theoretical electro-optic response from 13.5 GHz to 52.8 GHz. Due to the high modulation efficiency from the Quantum Confined Stark Effect (QCSE) in quantum wells, the traveling wave modulator is very compact with a length of only 600 μm.