| 摘要 |
PURPOSE:To realize laser oscillation and amplification action having excellent efficiency by adding a rare earth element to a core wavegudie and a clad. CONSTITUTION:A buffer layer 2 having a refractive index of nb is formed onto a substrate 1 composed of a semiconductor, glass, a ferrodielectric, a magnetic substance, etc., core waveguides 3-1 and 3-2 having a refractive index of nc (nc>nb) and an approximately rectangular cross section are shaped onto the layer 2, and the whole upper section of the core waveguides is covered with a clad 4 having a refractive index of ncl (ncl<nc). A rare earth element is added to the core waveguides 3-1, 3-2 and the clad 4. The waveguides 3-1 and 3-2 have adjacently arranged coupling sections 5, and an optical signal 6 mutually interferes and is propagated while shifting between the waveguides 3-1, 3-2, is transferred from one to the other in the wvaveguides in response to coupling length (l), and it divided into both waveguides. |
