An optical semiconductor - mach - zehnder - modulator with multiple quanta sources

摘要

PURPOSE: To provide a semiconductor Mach-Zehnder type modulator for optical communication and optical information processing which operates on a low voltage and is low in waveguide loss by using MOVPE selective growth technique. ;CONSTITUTION: A wafer which partially varies in band gap wavelengths is formed by one time of crystal growth if selective MOVPE growth is used. Easy varying of the band gap wavelength by ≥50meV by partially changing the width of a mask at the time of selective growth is possible. The band gap wavelength of a phase modulator part 122 is set on a slightly shorter wavelength side (λ_a) than the wavelength λOP of incident light. The band gap wavelength is settable at a wavelength of a small coefft. of absorption with the wavelength λOP of the incident light on the shorter wavelength side λ_a as 3dB branching part 121 and confluent part 123. Namely, the Mach-zehnder modulator of the low voltage and the low loss in realized at a good yield if the MOVPEs are selectively grown by using the mask of the width varying with the phase modulator part and 3dB branching part and confluent part and are set at the optimum band gap wavelengths.;COPYRIGHT: (C)1995,JPO