A GaAs Mode-Filter Type Light Intensity Modulator

Abstract

Electro-optic polarization modulation has been studied at 1.15μm in a waveguide structure formed in a Ga As reverse-biased p⁺ nn⁺ junction diode and a Schottky junction diode. For the p⁺ nn⁺ junction type, polarization modulation showed a satisfactory result with an incident beam polarization angle of 45° to the {100} crystal axis, while for the Schottky junction type, sufficient result was not obtained due to its waveguide transmission loss in a metal-clad waveguide. As for the application of the metal-clad, mode-filter type light intensity modulation was investigated in a unified Schottky junction structure of modulator-and analyzer-sections using the metal-clad with {110} crystal axis.