Provided is a laser device according to embodiments of the inventive concept comprising a substrate including a gain region, a phase control region, and a tuning region arranged along a first direction, the substrate having an air gap which extends from the phase control region to the tuning region, an upper clad layer on the substrate, a waveguide structure extending in the first direction between the upper clad layer and the substrate, a first upper electrode disposed on the upper surface of the upper clad layer of the tuning region, and a lower electrode disposed on a lower surface of the substrate and extending from the gain region to the tuning region, wherein the air gap may have a larger width than the waveguide in a second direction crossing the first direction.

The teachings herein disclose a laser assembly (20) that implements a composite cavity formed in part in a III/V die (22), in part in a silicon die (26), and in part in a glass member (24) having a waveguide (44) coupling the cavity portion in the III/V die with the cavity portion in the silicon die. This arrangement capitalizes on the lasing efficiency of the III/V die, which is used as the gain medium while advantageously using the glass member to extend the lasing cavity into the silicon die. Laser-scribing the cavity waveguide in place after mounting the III/V die, the silicon die or dies, and the glass member, greatly relaxes the mounting alignment precision needed for the constituent parts of the overall assembly. Moreover, in one or more embodiments, glass member includes one or more laser-scribed waveguides operative as optical interconnects going between two or more silicon dies.

Embodiments of an optical modulator device are described. An example optical modulator includes a ridge laser configured to emit light, a ridge waveguide configured to transition between a transparent state and an absorbing state, and a waveguide tap formed between the ridge laser and the ridge waveguide. The waveguide tap is configured to optically couple a fraction of light generated in the ridge laser to the ridge waveguide. In the transparent state of the ridge waveguide, the ridge waveguide is configured to output the fraction of light for interference with light emitted from the ridge laser. In the absorbing state of the ridge waveguide, the ridge waveguide is configured to absorb the fraction of light. Depending upon whether the fraction of light is output from the ridge waveguide for interference, the output power of the laser seen at the far-field of the optical modulator can be modulated for data communications.

Aspects of the present disclosure describe systems, methods, and structures that advantageously amplify optical signals through the effect of optical pump signals generated by a multicore laser diode and multicore rare-earth doped optical fiber in optical communication with a 3D waveguide structure and a multicore input signal fiber providing a plurality of optical signals for amplification.

Embodiments of the present disclosure are directed to multi-wavelength laser generator may produce light with a frequency comb having equally spaced frequency lines. In various embodiments, the laser generator includes first, a semiconductor gain element is used to provide gain to the laser being generated. Second, a ring resonator filter, or ring filter, is used to select the wavelength comb spacing. Third, a narrow-band DBR or narrow-band mirror is used to select the number of wavelengths that lase. Fourth, a wide-band or narrow-band mirror is used to provide optical feedback and to form the optical cavity. Fifth, a phase tuner section is used to align the cavity modes with the ring resonances (i.e. the ring filter modes) in order to reduce or minimize the modal loss. Other embodiments may be described and/or claimed.

An artificial saturable absorber uses additive pulse mode-locking to enable pulse operation of an on-chip laser operation. Four different artificial saturable absorbers are disclosed. The first includes an integrated coupler, two arms each containing some implementation of the end-reflector, and a phase bias element in one arm. The second includes an integrated directional coupler, two integrated waveguide arms, and another integrated coupler as an output. The third includes an integrated birefringent element, integrated birefringent-free waveguide, and integrated polarizer. And the fourth includes a multimode waveguide that allows for different modes to propagate in such a way that the difference in the spatial distribution of intensity causes a nonlinear phase difference between the modes. These are just some examples of an on-chip fully integrated artificial saturable absorber with instantaneous recovery time that allow for generation of sub-femtosecond optical pulses at high repetition rates using passive mode-locking.

A apparatus includes a tunable laser configured to include a tunable filter and a mirror; a first optical splitter provided between the tunable filter and the mirror, the first optical splitter including a first port and a second port on a tunable filter side and a third port and a fourth port on a mirror side, in which the tunable filter is coupled to the first port and the mirror is coupled to the third port, respectively; a first optical waveguide coupled to the second port; a second optical waveguide coupled to the fourth port; and an optical coupler with which the first optical waveguide and the second optical waveguide are combined.

A tunable solid state laser device are described comprising a semiconductor based gain chip and a silicon photonic filter chip with tuning capability. The silicon photonic filter chip can comprises an input-output silicon waveguide, at least two ring resonators formed with silicon waveguides, one or more connecting silicon waveguides interfacing with the ring resonators, a separate heater associated with each ring resonator, a temperature sensor configured to measure the chip temperature, and a controller connected to the temperature sensor and the separate heaters and programmed with a feedback loop to maintain the filter temperature to provide the tuned frequency. The one or more connecting silicon waveguides are configured to redirect light resonant with each of the at least two ring resonators back through the input-output silicon waveguide. Corresponding methods are described for the control of the laser frequency. Improved structures of the SiPho multiple filter chip involve a Zagnac interferometer.

Embodiments of the present invention provide an optical signal modulation apparatus and system. The optical signal modulation apparatus includes: a laser, where each of at least one first output end and at least one second output end of the laser is connected to an electro-absorption modulator (EAM), the laser is configured to generate at least two optical signals, where at least one of the optical signals is sent to at least one EAM by using the at least one first output end, and at least one of the optical signals is sent to at least one EAM by using the at least one second output end, and each EAM is configured to modulate a received electrical signal onto the received optical signal for outputting. The apparatus has a simple structure and less complex production.

A laser apparatus is provided, comprising a semiconductor substrate, an active layer disposed on the semiconductor substrate, a folded waveguide disposed on the active layer and forming a resonant structure, the folded waveguide comprising at least two substantially straight waveguide portions coupled by a connecting waveguide structure, with the folded waveguide having a first end and a second end located at one or more edges of the semiconductor substrate, wherein at least one of the ends includes a mirror, and an electrode coupled to the folded waveguide and configured to create photons in the folded waveguide when receiving electrical power. The waveguide emits laser light comprising the photons, with the laser light emitted at an edge of the semiconductor substrate.