Monolithic optical gates based on integration of evanescently-coupled uni-traveling-carrier photodiodes and electroabsorption modulators

We report on chip-scale optical gates based on the integration of evanescent waveguide unitraveling-carrier photodiodes (EC-UTC-PDs) and intra-step quantum well electroabsorption modulators (IQW-EAMs) on n-InP substrates.These devices exhibit simultaneously 2.1 GHz and 16.2 dB RF-gain at 21 GHz with a 450 thin-film resistor and a bypass capacitor integrated on a chip.     

Design of novel three port optical gates scheme for the integration of large optical cavity electroabsorption modulators and evanescently-coupled photodiodes

This paper presents a novel scheme to monolithically integrate an evanescently-coupled uni-travelling carrier photodiode with a planar short multimode waveguide structure and a large optical cavity electroabsorption modulator based on a multimode waveguide structure. By simulation, both electroabsorption modulator and photodiode show excellent optical performances. The device can be fabricated with conventional photolithography, reactive ion etching, and chemical wet etching.     

一种利用光电流和光透过曲线测量电吸收调制器插入损耗因素的方法

提出一种新颖的方法用于测量电吸收调制器（electroabsorption modulator,EAM）各种因素造成的插入损耗.此方法仅需要测量波长相关的光电流（I_ph-λ）和光透过功率（P-λ）的数据,通过最小二乘法拟合出结果.理论分析表明此方法较精确,实验表明测试结果与理论拟合结果自洽得很好. 关键词： 电吸收调制器 插入损耗 吸收曲线 光生电流     

High-performance evanescently-coupled uni-traveling-carrier photodiodes

A new evanescently-coupled uni-traveling-carrier photodiode (EC-UTC PD) based on a multimode diluted waveguide (MDW) structure is fabricated, analysed and characterized. Optical and electrical characteristics of the device are investigated. The excellent characteristics are demonstrated such as a responsivity of 0.36~A/W, a bandwidth of 11.5~GHz and a small-signal 1-dB compression current greater than 18~mA at 10~GHz. The saturation current is significantly improved compared with those of similar evanescently-coupled pin photodiodes. The radio frequency (RF) bandwidth can be further improved by eliminating RF losses induced by the cables, the probe and the bias tee between the photodiode and the spectrum analyzer.