A laser includes first and second feedback elements defining a laser cavity, and a gain medium within the laser cavity. The gain medium has first and second facets and an optical waveguide for guiding optical radiation between said first and second facets. The second feedback element is wavelength selective, and the optical waveguide is configured to direct optical radiation at an angle .theta. to the normal of the second facet.
An integrated optical component having a first section (S1) including a wave guide (10) perpendicular to an output facet (P) of the component, a termination (T) of the wave guide being coupled to this facet, and including a second section (S2) upstream from the first section and capable of being interfered with by the signal reflected by the said facet and guided by the wave guide. The guide termination (T) includes an inclined guiding section (13) and a laterally non-guiding section (14) leading to this facet (P).
A pump laser diode for providing improved stability at various operating temperatures is disclosed. It includes a Fabry-Perot cavity formed by laser facets. Bragg Gratings or Fiber Bragg Gratings (FBG) in a pump module are provided, wherein the optical mirror losses are made to increase for wavelengths longer than the required emission wavelength, thus permitting the diode to be locked to an emission wavelength while operating at different temperatures. A stack of materials with different refractive indices is deposited on the back facet of the laser diode to achieve a change in optical mirror losses over longer wavelengths.
Systems and methods according to the present invention address this need and others by providing SLD devices and methods for generating optical energy that reduce internal reflections without the use of an absorber region. This can be accomplished by, among other things, adapting the waveguide geometry to dump reflections from the front facet out through the back facet of the device.
A semiconductor optical device which has a ridge structure includes a waveguide area between paired mesa trenches; first and second mount areas disposed outside the mesa trenches; a first spacer layer disposed in a first mount area and a second spacer layer disposed in a second mount area; a first metal layer electrically connected to an upper cladding layer in the waveguide area and extending from the waveguide area over the first mount area; and a second metal layer disposed over the second mount area. Thicknesses from a back surface of the semiconductor optical device to the first metal layer in the first mount area and to the second metal layer in the second mount area are both larger than thickness from the back surface to the first metal layer in the waveguide area.
A distributed feedback laser device comprises an optical waveguide having one end facet serving as a beam emission surface and the other end facet serving as a reflection surface, an active layer formed between the beam emission surface and the reflection surface, and a diffraction grating formed so as to extend along the active layer in the optical waveguide. The active layer has a first region located nearer to the beam emission surface than to the reflection surface and a second region located nearer to the reflection surface than to the beam emission surface. The first region is narrower in width than the second region. The diffraction grating has first and second portions located along the first and the second regions, respectively. The first portion is longer in pitch than the second portion.
