| 摘要 |
<p>PURPOSE:To obtain a structure suitable to hybrid integration by providing a phase control function to at least one of the optical amplification area and optical waveguide areas on both its sides of the optical amplifying element which has nonreflective coats at both ends of the element to reduce the end surface reflection factor. CONSTITUTION:An active layer 1 is tapered gently at the borders of the active layer 1 and optical waveguide layers 2A and 2B formed across the active layer so as to prevent reflection and increase the optical coupling efficiency between both layers. Further, the optical amplification area where the layer 1 is formed is provided with nonreflective coats 8 on both end surfaces and then a current is injected to at least either of the optical waveguide areas at both ends. Consequently, the optical waveguide layer is varied in refractive index to control the phase difference of signal light propagated in the optical amplifying element. Therefore, when the hybrid integration is performed with various optical waveguides including a quartz-based optical waveguide, a >=20dB amplification factor is obtained stably among the optical waveguide, optical amplifying element, and optical waveguide.</p> |
