| 摘要 |
PURPOSE:To change an oscillation wavelength by a method wherein one part of a waveguide layer is held by a superlattice and a diffraction grating, an active layer is formed through a phase matching section in the longitudinal direction to these superlattice and diffraction grating, voltage is applied to the superlattice and the refractive index of the superlattice is altered. CONSTITUTION:A waveguide layer (such as a waveguide layer 3) extending over overall length in the longitudinal direction and shaping a laser resonator, a superlattice (such as a superlattice 5) and a diffraction grating (such as a diffraction grating 2) holding the waveguide layer and extending in length selected in the longitudinal direction from sections near one laser-beam reflecting surface, and an active layer (such as an active layer 4) spreading toward a section near the other laser-beam reflecting surface, interposing a phase matching section (such as a phase matching section M) in the longitudinal direction to the superlattice and the diffraction grating and being disposed near the waveguide layer are formed. Consequently, when beams are propagated in the optical guide, not only the real part of the optical guide but also the imaginary part thereof change in a refractive index in the superlattice when external applied voltage is fluctuated. Accordingly, an oscillation wavelength can stably be altered largely by voltage applied to a control electrode. |
