Very low input voltage cascaded travelling wave electroabsorption modulator (CTWEAM) for more than 100 Gbps

This paper presents the large signal modeling and simulation of two segmented travelling wave electroabsorption modulators (TWEAM) as a cascaded TWEAM (CTWEAM) structure. It will be demonstrated that a mushroom shaped mesa structure with low series resistance (0.69 Ω-mm) will have 3 dB bandwidth more than sufficient for 100 Gbps operation. For a CTWEAM device with 990 μm active segment length, 1.1 V bias voltage and only 0.4 V peak-to-peak (Vp–p) modulating voltage has a bandwidth of 110 GHz, extinction ratio >4 dB and flat frequency response. This device would be an attractive candidate for short distance optical fiber communication as well as long distance telecommunication at 0.4 Vp–p and 1 Vp–p input RF signal, respectively.