Semiconductor laser device

Abstract

Abstract PURPOSE:To output an optical signal having a desired electromagnetic component with almost no increase in threshold current value and no decrease in differential quantum efficiency, by selectively passing only the light having the specified electromagnetic component, and providing a layer which can control the intensity of the passing light by changing refractive index with a current or voltage that is applied from a signal source. CONSTITUTION:When a TE wave and a TM wave are guided from the left side, an electric field which is in parallel with the surface of an electrode 109 is absorbed. Therefore, the TE wave is attenuated as shown by an attenuated TE wave 204. The TM wave is reflected as a TM reflected wave 203. Therefore, only the TM wave is selectively oscillated. When, a current is injected from a left electrode, the refractive index in a waveguide 103A is decreased. Therefore, a resonant wavelength in a right diffraction grating 106B is changed. The reflectivity for the wavelength, which is regulated with a right diffraction grating 106A, is decreased. Therefore, the intensity of the output light is changed. Namely, the waveguide 103A has a layer having the following two functions : a mode selecting function; and a function which changes the refractive index of the waveguide itself and changes the intensity of the output light. Thus, the optical signal of the TM wave can be inputted into a logic element, which is optically coupled with the element with the waveguide 103.

Inventors

• 👤 Yoshihiro Mori
• 👤 Atsushi Shibata

Bibliographic Details