Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission.

A semiconductor optical device includes a substrate having an optical waveguide, a gain section formed of a compound semiconductor having an optical gain and bonded to an upper surface of the substrate, the gain section having a first mesa, and a first wiring line electrically connected to the gain section. The first mesa of the gain section is optically coupled to the optical waveguide. The substrate includes a first layer, a second layer, and a third layer. The first layer has a higher thermal conductivity than the second layer. The second layer is stacked on the first layer. The third layer is stacked on the second layer. A recess provided in the substrate extends through the third layer to the second layer in the thickness direction. The first wiring line extends from the first mesa of the gain section to the recess.

An external cavity diode laser has been developed to achieve a linear frequency chirp over a broad bandwidth using a silicon photonic filter chip as the external cavity. By appropriately chirping the cavity phase using the gain chip and/or a cavity phase modulator on the silicon photonic chip along with simultaneously varying the filter resonance, approximately linear frequency chirping can be accomplished for at least 50 GHz, although desirable structures with useful lesser chirp bandwidths are also described. With careful control of the chip design, it is possible to achieve predictable behavior of mode jumps along with large scannable ranges within a mode, which allows for stitching together segments of linear chirp through a mode jump to provide for very large chirp bandwidths greater than 1 THz.

A novel, monolithically integrated mid-IR optical phased array (OPA) structure which eliminates the wafer bonding process to achieve highly efficient surface emitting optical beam steering in two dimensions is disclosed. Since solar energy is about 15-20 times smaller than that at 1.55 μm, mid-IR is more favorable for the atmospheric transmission due to lower solar radiance backgrounds. For the beam steering, thermo-optic phase shifting is used for azimuthal plane beam steering and laser wavelength tuning is used for elevation plane beam steering. The OPA structure disclosed comprises a wavelength-tunable a QCL, a 1×32 splitter, thermo-optic phase-shifters, and sub-wavelength grating emitters. The disclosed OPA provides a low-cost, low-loss, low-power consumption, robust, small footprint, apparatus that may be used with expendable UAV swarms. A LiDAR may be created by monolithically integrating a QCD with the apparatus. Other embodiments are described and claimed.

The present invention concerns a tunable Dense Wavelength Division Multiplex (DWDM) intra cavity laser device having a first optical wave guide having a first optical grating section, a second optical wave guide having a second optical grating section, an active gain section spatially separated from the second optical grating section and a phase section, and a DWDM-filter having an intra-cavity ring resonator located between the first optical wave guide and the second optical wave guide for coupling optical waves between the first and second optical wave guides. The tunable laser device is tunable in a discrete manner depending on a length of the ring resonator that is selected such that the free spectral range of the ring resonator matches a predetermined fixed wavelength spacing grid.

There are provided a first cladding layer formed on a Si substrate, a first core made of Si and formed on the first cladding layer, and a second cladding layer formed on the first cladding layer and covering the first core Additionally, this optical device includes a waveguide type laser formed over the second cladding layer, a second core made of InP and formed continuously to the laser, and a third cladding layer formed on the second cladding layer and covering the laser and the second core.

Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission.

An optical device including a waveguide grating is disclosed. The optical device may be used as an optical cavity for a laser device, for instance, of an integrated laser device for light detection and ranging (Lidar) applications. In one aspect, the optical device includes a waveguide grating for guiding light, a heating layer provided beneath or above the waveguide grating, and two or more contacts for passing a current through the heating layer, to generate heat in the heating layer. The heating layer is thermally coupled to the waveguide grating and is optically decoupled from the waveguide grating.

A method for on-silicon integration of a III-V-based material component includes providing a first substrate having a silicon-based optical layer including a waveguide, transferring a second substrate of III-V-based material on the optical layer, and forming the III-V component from the second substrate, so as to enable a coupling between the waveguide and the III-V component, by preserving a III-V-based material layer extending laterally. The method also includes forming by epitaxy from the III-V layer, an InP:Fe-based structure laterally bordering the III-V component, forming a layer including contacts configured to contact the III-V component, and transferring a third silicon-based substrate onto the layer including the contacts.

Examples described herein relate to an optical device with an integrated light-emitting structure to generate light and a waveguide integrated capacitor to monitor light. The light-emitting structure may emit light upon the application of electricity to the optical device. The waveguide integrated capacitor may be formed under the light-emitting structure to monitor the light emitted by the light-emitting structure. The waveguide integrated capacitor includes a waveguide region carrying at least a portion of the light. The waveguide region includes one or more photon absorption sites causing the generation of free charge carriers relative to an intensity of the light confined in the waveguide region resulting in a change in the conductance of the waveguide region.