A laser includes a substrate, first and second claddings, a gain medium, and multiple supports. The first cladding is spaced apart from the substrate by an air gap. A thickness of the first cladding in a vertical direction is in a range from 0.05-0.15 micrometers. The gain medium is disposed on the first cladding opposite the air gap. The second cladding is disposed on the gain medium opposite the first cladding. A thickness of the second cladding in the vertical direction is in a range from 0.05-0.15 micrometers. The supports are coupled to each of the substrate, the first cladding, the gain medium, and the second cladding to retain the first cladding, the gain medium, and the second cladding spaced apart from the substrate.

A spot-size converter includes first and second waveguide structures. The first waveguide structure extends longitudinally along a waveguide axis from a first end to a second end and is configured to support a first optical mode at the first end. The second waveguide structure is formed within the first waveguide structure. The second waveguide structure extends longitudinally between the first end and the second end. The second waveguide structure is configured to support a second optical mode at the second end. The second optical mode has a different diameter than the first optical mode. The second waveguide structure includes a waveguide core that has a first cross-sectional area in a first plane normal to the waveguide axis at the first end and a second cross-sectional area in a second plane normal to the waveguide axis at the second end. The second cross-sectional area is larger than the first cross-sectional area.

This application provides a two-segment DBR laser and a monolithically integrated array light source chip, and relates to the field of optical communications. The two-segment DBR laser includes a grating region, a gain region, and a broadband reflector. The grating region and the broadband reflector are respectively disposed at two ends of the gain region. The grating region includes a first bottom liner, a first support structure, a first ridge waveguide structure, and a first heater. The first ridge waveguide structure is fastened by the first support structure and suspended in midair above the first bottom liner, and the first bottom liner, the first support structure, and the first ridge waveguide structure jointly form a cavity. The first heater is located on a surface that is of the first ridge waveguide structure and that faces away from the cavity.

The present disclosure relates to a three-dimensional cylindrical cavity-type laser system capable of supporting circumferential radial emission. A cylindrical ring waveguide provides optical confinement in the radial and axial dimensions thereby supporting a plurality of radial modes, one of a plurality of axial modes and a plurality of degenerate azimuthal modes. These modes constitute a set of traveling wave modes which propagate around the cylindrical ring waveguide possessing various degrees of optical confinement as quantified by their respective Q-factors. Index tailoring is used to tailor the radial refractive index profile and geometry of the waveguide to support radial modes possessing Q-factors capable of producing efficient radial emission, while gain tailoring is used to define a gain confining region which offsets modal gain factors of the modal constituency to favor a preferred set of modes supporting efficient radial emission out of the total modal constituency supported by the resonator. Under appropriate pump actuation the selected modes produce circumferential laser radiation with the output surface comprising of the entire outer perimeter of the cylindrical ring waveguide. The design is applicable toward both micro-resonators and resonators much larger than the optical wavelength, enabling high output powers and scalability. The circumferential radial laser emission can be concentrated by positioning the cylindrical ring laser inside a three-dimensional conical mirror thereby forming a laser ring of light propagating in the axial dimension away from the surface of the laser, which can be subsequently collimated for focused using conventional optics.

An integrated photonic structure and a method of fabrication includes a substrate having at least one opening disposed therein; a semiconductor stack disposed above the substrate, the semiconductor stack being, at least in part, isolated from the substrate by an opening to define a suspended semiconductor membrane; and a first doped region and a second doped region located within the suspended semiconductor membrane. The first doped region is laterally separated from the second doped region by an optically active region disposed therein that defines a waveguiding region of the integrated photonic structure.

According to an embodiment, a wavelength tunable laser comprising a gain region and a wavelength tunable area is disclosed. The wavelength tunable area comprises: a lower clad layer; a passive optical waveguide positioned on the lower clad layer; an upper clad layer positioned on the passive optical waveguide; a drive electrode positioned on the upper clad layer; a current blocking layer positioned on the drive electrode; a heater positioned on the current blocking layer; and a first insulating groove and a second insulating groove which are positioned so as to face each other with the passive optical waveguide therebetween.

A wavelength tunable laser includes: a heating layer, a dielectric layer, reflectors, a transport layer, a support layer, and a substrate layer. The heating layer is located above the transport layer; the transport layer is located above the support layer, and the transport layer includes an upper cladding layer, a waveguide layer, and a lower cladding layer from top to bottom; the reflector is located in the transport layer; the support layer has a protection structure, where the protection structure forms a hollow structure together with the transport layer and the substrate layer, and the hollow structure has a support structure; and the substrate layer is located below the support layer. The heating layer, the reflector, and a part of the transport layer form a suspended structure to prevent heat dissipation. Thus thermal tuning efficiency can be improved, and power consumption can be lowered.

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 device comprises a substrate, a sacrificial material layer over the substrate, a first solid-state material layer over the sacrificial layer, a dielectric layer over solid-state material layer, and a second solid-state material layer over the dielectric layer. The sacrificial material layer may have an airgap, the solid-state material layer may comprise a structure over the airgap and may be separated from a bulk portion of the first material layer by trenches, where the trenches extend to the airgap.

An integrated photonic structure and a method of fabrication includes a substrate having at least one opening disposed therein; a semiconductor stack disposed above the substrate, the semiconductor stack being, at least in part, isolated from the substrate by an opening to define a suspended semiconductor membrane; and a first doped region and a second doped region located within the suspended semiconductor membrane. The first doped region is laterally separated from the second doped region by an optically active region disposed therein that defines a waveguiding region of the integrated photonic structure.