A laser device includes front and back DBRs and an interferometer. The front DBR is coupled to a front DBR electrode. The front DBR forms a first tunable multi-peak lasing filter. The back DBR is coupled to a back DBR electrode. The back DBR forms a second tunable multi-peak lasing filter. The interferometer part is coupled between the front DBR and the back DBR. The interferometer part includes first and second waveguide combiners and first and second interferometer waveguides coupled therebetween. The first waveguide combiner couples the interferometer part to the back DBR. The second waveguide combiner couples the interferometer part to the front DBR. The first interferometer waveguide is coupled to an interferometer electrode. The interferometer forms a third tunable multi-peak lasing filter.

A laser includes a substrate and a resonant cavity. In addition to an active gain region, a first phase shift region, an optical branching region, and N reflective mode selection regions, the resonant cavity further includes a highly reflective surface, where a reflectivity of the highly reflective surface is greater than reflectivities of the N reflective mode selection regions, so that laser beams are output from the N reflective mode selection regions. Because the laser naturally includes at least two reflective mode selection regions, at least two laser beams are output. According to the laser provided by the embodiments of the present invention, one laser can output two laser beams or even multiple laser beams; therefore, laser beam generation efficiency is high and average costs for generating a single laser beam are accordingly reduced.

Apparatuses including integrated circuit (IC) optical assemblies and processes for operation of IC optical assemblies are disclosed herein. In some embodiments, the IC optical assemblies include a transmitter component to provide light output having a particular beam direction, and a transmitter driver component. The transmitter component includes a light source optically coupled to a plurality of waveguides, a plurality of gratings, and a plurality of phase tuners. The transmitter driver component causes a light provided by the light source to be centered at a particular wavelength and a particular phase to be induced by each phase tuner of the plurality of phase tuners on a respective waveguide of the plurality of waveguides, in accordance with a feedback signal, to generate the light output having the particular beam direction.

A parallel cavity tunable laser generally includes a semiconductor laser body defining a plurality of parallel laser cavities with a common output. Each of the parallel laser cavities is configured to be driven independently to generate laser light at a wavelength within a different respective wavelength range. The wavelength of the light generated in each of the laser cavities may be tuned, in response to a temperature change, to a channel wavelength within the respective wavelength range. The laser light generated in each selected one of the laser cavities is emitted from the common output at a front facet of the laser body. By selectively generating light in one or more of the laser cavities, one or more channel wavelengths may be selected for lasing and transmission.

A distributed feedback plus reflection (DFB+R) laser includes an active section, a passive section, a low reflection (LR) mirror, and an etalon. The active section includes a distributed feedback (DFB) grating and is configured to operate in a lasing mode. The passive section is coupled end to end with the active section. The LR mirror is formed on or in the passive section. The etalon includes a portion of the DFB grating, the passive section, and the LR mirror. The lasing mode of the active section is aligned to a long wavelength edge of a reflection peak of the etalon.

A reflector structure for a tunable laser and a tunable laser. A super structure grating is used as a reflector structure, and a suspended structure is formed around a region in which the super structure grating is located, to implement, using the suspended structure, thermal isolation around the region in which the super structure grating is located, and increase thermal resistance, such that less heat is lost, and heat is concentrated in the region in which the super structure grating is located, thereby improving thermal tuning efficiency of the reflector structure. Moreover, lateral support structures are disposed on two sides of the suspended structure, to provide a mechanical support for the suspended structure. In addition, regions in the super structure grating that correspond to any two lateral support structures on a same side of the suspended structure fall at different locations in a spatial period of the super structure grating.

A QCL may include a substrate, and a semiconductor layer adjacent the substrate. The semiconductor layer may define branch active regions, and a stem region coupled to output ends of the branch active regions. Each branch active region may have a number of stages less than 30.

An optical transmission apparatus includes a first multilevel optical phase modulator and a first semiconductor optical amplifier. The first semiconductor optical amplifier includes a first active region having a first multiple quantum well structure. Assuming that a first number of layers of a plurality of first well layers is defined as n.sub.1 and a first length of the first active region is defined as L.sub.1 (μm): (a) n.sub.1=5 and 400≤L.sub.1≤563; (b) n.sub.1=6 and 336≤L.sub.1≤470; (c) n.sub.1=7 and 280≤L.sub.1≤432; (d) n.sub.1=8 and 252≤L.sub.1≤397; (e) n.sub.1=9 and 224≤L.sub.1≤351; or (f) n.sub.1=10 and 200≤L.sub.1≤297.

A wavelength-tunable laser device includes: a wavelength-tunable light source part; an optical filter; a light receiving element; and a control device. Further, the control device includes: a monitor value calculating part configured to calculate a monitor value; a storage part configured to store wavelength control information; a target value calculating part configured to calculate a control target value; and a wavelength control part configured to control the wavelength of the laser beam to be the target wavelength, and the wavelength control information is information in which a wavelength, a control reference value, and mode identification information are associated with each other, and the target value calculating part calculates the control target value based on the wavelength control information stored in association with the same mode identification information when the same wavelength as the target wavelength is different from the wavelength control information stored in the storage part.

A semiconductor optical integrated device in which a forward-bias optical device and a semiconductor laser are monolithically integrated on a semiconductor substrate, includes: a passive waveguide portion that is arranged between the forward-bias optical device and the semiconductor laser; and a ground electrode that is arrange on a lower surface of the semiconductor substrate. Further, the semiconductor laser includes a mirror having a length on a side closer to the forward-bias optical device, the forward-bias optical device includes a forward-bias optical-device electrode on a side opposite to a side in contact with the semiconductor substrate, the passive waveguide portion includes a passive waveguide electrode on a side opposite to a side in contact with the semiconductor substrate, and the passive waveguide electrode is electrically connected to the ground electrode.