A new light modulator using perturbation of synchronism between two coupled guides

Abstract

A new device that can be used as a light modulator as well as an optical directional coupler is proposed. It consists of p⁺,n,n⁺,n and n⁺‐type semiconductor layers. Two n‐type layers operate as coupled optical waveguides. The exchange of light power between two coupled waveguides can be controlled by a reverse voltage applied on the p⁺‐n junction. When the voltage was changed from 0 to 10 V in a GaAs test sample of length 1 mm, the output light power from each guide changed by approximately 15% of the total output light power from the two guides at a wavelength of 1.15 μm.