A system includes a waveguide and an edge-emitting laser. The edge-emitting laser is configured to lase coherent light into the waveguide. The edge-emitting laser includes an optical cavity having an active gain section and a passive section. The active gain section is configured to amplify an optical power of light reflecting within the optical cavity. The passive section increases a functional length of the optical cavity such that a total length of the optical cavity reduces fringe interference of the coherent light propagating through the waveguide.

A mode-locked semiconductor laser capable of changing the spacing between the carrier frequencies of its output comb. In an example embodiment, the mode-locked semiconductor laser is implemented as a hybrid solid-state device comprising a III-V semiconductor chip and a silicon chip attached to one another to form a laser cavity. The III-V semiconductor chip includes a gain medium configured to generate light in response to being electrically and/or optically pumped. The silicon chip includes a plurality of optical waveguides arranged to provide multiple optical paths of different effective lengths for the light generated in the laser cavity. Different optical paths can be controllably selected, using one or more optical switches connected between the optical waveguides, to change the effective optical length of the laser cavity and, as a result, the output-comb frequency spacing. In some embodiments, the output-comb frequency spacing can be changeable at least by a factor of 1.5.

A laser module that can suppress influence due to a reflected light between chips is provided. A laser module 100 according to one embodiment of the present invention includes: a laser element 110 provided on a first substrate and having a laser oscillation unit that generates a laser light and a first optical waveguide that guides the laser light; and an optical amplifier 120 provided on a second substrate and having a second waveguide that guides the laser light. The first optical waveguide is nonparallel relative to an end face of the first substrate and connected thereto, the second optical waveguide is nonparallel relative to an end face of the second substrate and connected thereto, and the first substrate and the second substrate are arranged such that the laser light output from the first optical waveguide is optically coupled to the second optical waveguide.

The present invention discloses an integrated broadband chaotic semiconductor laser using optical microcavities. The arc-shaped hexagonal laser outputs light. Part of the light is totally reflected through the deformed microcavity and then reflected out of the deformed microcavity from the passive waveguide II; after entering the passive feedback waveguide, another part of the light is fed back into the deformed microcavity by the high reflection film, passes through an in-cavity ray track and then is also reflected out of the deformed microcavity from the passive waveguide II; the two-path light is coupled into the arc-shaped hexagonal laser, and finally generated chaotic laser light is directionally coupled and output through the passive waveguide I at the other end of the arc-shaped hexagonal laser. The present invention has wide broadband, flat spectrum, compact structure, and no time delay signature.

Disclosed are photonic particles and methods of using particles in biological samples. The particles are configured to emit laser light when energetically stimulated by, e.g., a pump source. The particles may include a gain medium with inorganic materials, an optical cavity with high refractive index, and a coating with organic materials. The particles may be smaller than 3 microns along their longest axes. The particles may attach to each other to form, e.g., doublets and triplets. The particles may be injection-locked by coupling an injection beam into a particle while pumping so that an injection seed is amplified to develop into laser oscillation. A microscopy system may include a pump source, beam scanner, spectrometer with resolution of less than 1 nanometer and acquisition rate of more than 1 kilohertz, and spectral analyzer configured to distinguish spectral peaks of laser output from broadband background.

An edge-emitting laser including a substrate, a lower power optical cavity located on the substrate and a higher power optical cavity located on the substrate adjacent the lower power optical cavity. The lower power optical cavity includes a first active gain section having a first length. The higher power optical cavity includes a second active gain section having a second length greater than the first length.

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 front facet of the semiconductor laser device includes a resonator facet portion containing an end of an active layer, and a protruding portion which protrudes beyond the resonator facet portion in a resonator length direction by a predetermined protrusion amount and has a stepped bottom surface portion. The resonator facet portion and the stepped bottom surface portion are connected to each other to form a corner portion. The distance from a thickness center position of the active layer to the stepped bottom surface portion is defined by a bottom surface portion depth. The bottom surface portion depth is set to be equal to a predetermined specific depth or deeper than the specific depth.

Disclosed are photonic particles and methods of using particles in biological samples. The particles are configured to emit laser light when energetically stimulated by, e.g., a pump source. The particles may include a gain medium with inorganic materials, an optical cavity with high refractive index, and a coating with organic materials. The particles may be smaller than 3 microns along their longest axes. The particles may attach to each other to form, e.g., doublets and triplets. The particles may be injection-locked by coupling an injection beam into a particle while pumping so that an injection seed is amplified to develop into laser oscillation. A microscopy system may include a pump source, beam scanner, spectrometer with resolution of less than 1 nanometer and acquisition rate of more than 1 kilohertz, and spectral analyzer configured to distinguish spectral peaks of laser output from broadband background.

A tunable laser device based on silicon photonics includes a substrate configured with a patterned region comprising one or more vertical stoppers, an edge stopper facing a first direction, a first alignment feature structure formed in the patterned region along the first direction, and a bond pad disposed between the vertical stoppers. Additionally, the tunable laser includes an integrated coupler built in the substrate located at the edge stopper and a laser diode chip including a gain region covered by a P-type electrode and a second alignment feature structure formed beyond the P-type electrode. The laser diode chip is flipped to rest against the one or more vertical stoppers with the P-type electrode attached to the bond pad and the gain region coupled to the integrated coupler. Moreover, the tunable laser includes a tuning filter fabricated in the substrate and coupled via a wire waveguide to the integrated coupler.