The spectral linewidth enhancement factor and frequency responses of electro-absorption-type optical-intensity modulators, especially InGaAs/InAlAs MQW modulators, are described. A method of exactly estimating the value of the alpha factor is presented under the nonlinearity of extinction-ratio characteristics. For measuring the frequency response of modulators, the sideband strength of the modula...Show More
High-speed phase modulation of waveguided InGaAs/InAlAs multiple-quantum-well optical modulators operating at 1.55 mu m is described. The modulator requires a low voltage for pi -phase-shift (V/sub pi /=2.5 V) as well as a small intensity modulation depth of 1 dB. The measured electrical 3-dB bandwidth is 10 GHz, giving a bandwidth-to-voltage ratio of 4 GHz/V.<>Show More
