Structures for response shaping in frequency and time domain, include an optical response shaper and/or a modulator device with multiple injection. The device comprises a resonator having an enclosed geometric structure, for example a ring or racetrack structure, at least two injecting optical waveguides approaching the resonator to define at least two coupling regions between the resonator and the injecting waveguides, and may define at least two Free Spectral Range states.

One or both of the coupling regions has a coupling coefficient selected for a predetermined frequency or time response, and the coupling coefficient or other device parameters may be variable, in some case in real time to render the response programmably variable.

A ring-resonator filter device includes: a waveguide device that includes a core. Further, the core constitutes two ring resonator filters, each of the two ring resonator filters includes two arm portions, a ring-shaped portion, and two optical coupling/branching portions that optically couple the two arm portions and the ring-shaped portion, respectively, and the two ring-shaped portions cross each other.

A laser includes a distributed Bragg minor and is configured to emit monochromatic light radiation along a longitudinal direction. The laser has layers, stacked along a first transverse direction normal to the longitudinal direction and made of III-V materials, including an active region configured to emit the radiation. The mirror is formed by periodic lateral corrugations which extend mainly along the longitudinal direction and having a dimension along a second transverse direction normal to the longitudinal direction. The lateral corrugations of the Bragg minor extend from a top surface of the waveguide pattern along the first transverse direction on a height strictly less than the depth, at which the active region is located starting from the top surface, such that a portion of lateral flanks of the waveguide is free of any lateral corrugations at the active region.

A cylindrical electrode module of a fiber optic laser system includes an inner cylinder having an inner repeating pattern of longitudinally-aligned positive and negative electrodes on an outer surface of the inner cylinder. The cylindrical electrode mode includes an outer cylinder that encloses the inner cylinder. The outer cylinder that has an outer repeating pattern of longitudinally-aligned negative and positive electrodes on an inner surface of the inner cylinder that are in corresponding and complementary, parallel alignment with the positive and negative electrodes of the inner repeating pattern on the outer surface of the inner cylinder. The cylindrical electrode module includes an optical fiber having an input end configured to align with and be optically coupled to a pump laser. The optical fiber is wrapped around the inner cylinder within the outer cylinder to form a cylindrical fiber assembly. The electrodes are activated to achieve quasi-phase matching.

A laser comprising a narrow linewidth, comprising: a grating along a laser cavity; a laser waveguide having a plurality of waveguide sections corresponding to a plurality of grating sections, each of the plurality of waveguide sections having a ridge/mesa width for detuning the grating in each of the plurality of grating sections; and a plurality of contact electrodes contacting each of the plurality of waveguide sections, the plurality of contact electrodes for applying a different current to each of the plurality of waveguide sections to enable active feedback noise suppression.

A semiconductor optical device includes a substrate including a waveguide made of silicon and a semiconductor layer joined to the substrate so as to overlap the waveguide and including a diffraction grating formed of a first semiconductor layer and a second semiconductor layer having different refractive indices. The waveguide includes a bent portion and a plurality of straight portions that are connected to each other by the bent portion and that extend straight. The first semiconductor layer and the second semiconductor layer are each made of a compound semiconductor. The second semiconductor layer is embedded in the first semiconductor layer and includes a plurality of portions arranged in a direction in which the plurality of straight portions extend. The diffraction grating is positioned above the plurality of straight portions.

A germanium waveguide is formed from a P-type silicon substrate that is coated with a heavily-doped N-type germanium layer and a first N-type doped silicon layer. Trenches are etched into the silicon substrate to form a stack of a substrate strip, a germanium strip, and a first silicon strip. This structure is then coated with a silicon nitride layer.

A monolithic edge-emitting semiconductor diode array chip (100) comprises a one-dimensional array (70) of diode emitters (50), such as laser diodes, superluminescent diodes or semiconductor optical amplifiers. Semiconductor layers are arranged on a conductive substrate (1) and include active region layers (14) arranged between upper and lower cladding layers (12, 16) and separation layers (4, 5) arranged between the conductive substrate (1) and the lower cladding layer (16). The diode emitters (50) are formed by respective ridges (9) that are separated by trenches (25) which are sufficiently deep to penetrate into the separation layers (4, 5). Each diode (50) has its own upper and lower contacts (22, 24) that allow each diode (50) to be independently drivable with a current source driver circuit connected to push a modulated push current through its associated diode and/or a current sink connected to extract a modulated pull current through its associated diode.

An optical apparatus comprises a semiconductor substrate and an optical waveguide emitter. The optical waveguide emitter comprises an input waveguide section extending from a facet of the semiconductor substrate, a turning waveguide section optically coupled with the input waveguide section, and an output waveguide section extending to the same facet and optically coupled with the turning waveguide section. One or more of the input waveguide section, the turning waveguide section, and the output waveguide section comprises an optically active region.

A semiconductor laser device includes a first cladding including gallium nitride (GaN) on a substrate, a light waveguide on the first cladding, a first contact pattern, a first SCH pattern, a first active pattern, a second SCH pattern, a second cladding and a second contact pattern sequentially stacked on the light waveguide, and first and second electrodes on the first and second contact patterns, respectively.