The present invention relates to telecommunication techniques and integrated circuit (IC) devices. More specifically, embodiments of the present invention provide an off-quadrature modulation system. Once an off-quadrature modulation position is determined, a ratio between DC power transfer amplitude and dither tone amplitude for a modulator is as a control loop target to stabilize off-quadrature modulation. DC power transfer amplitude is obtained by measuring and sampling the output of an optical modulator. Dither tone amplitude is obtained by measuring and sampling the modulator output and performing calculation using the optical modulator output values and corresponding dither tone values. There are other embodiments as well.

A label-free biosensor detection arrangement incorporating an external cavity laser (ECL) includes a tunable lasing element (e.g. an antireflection coated laser diode or semiconductor optical amplifier) and a narrow bandwidth resonant reflectance filter as the wavelength-selective element for the tunable lasing element. A sample is deposited on the surface of the resonant reflectance filter containing a biological material. The wavelength emitted by the external cavity laser is continuously tunable by binding interactions between the biological material and the resonant reflectance filter or adsorption of the biological material present in the sample on resonant reflectance filter. The narrow bandwidth resonance reflectance filter can take the form of photonic crystal (PC), a Bragg stack, or a Brag fiber reflection filter.

A hybrid external cavity multi-wavelength laser using a QD RSOA and a silicon photonics chip is demonstrated. Four lasing modes at 2 nm spacing and less than 3 dB power non-uniformity were observed, with over 20 mW of total output power. Each lasing peak can be successfully modulated at 10 Gb/s. At 10.sup.−9 BER, the receiver power penalty is less than 2.6 dB compared to a conventional commercial laser. An expected application is the provision of a comb laser source for WDM transmission in optical interconnection systems.

An optical data communication system includes a plurality of resonator structures and a laser array that includes a plurality of lasers optically connected to the plurality of resonator structures. Each resonator structure has a respective free spectral wavelength range and a respective resonance wavelength. A maximum difference in resonance wavelength between any two resonator structures in the plurality of resonator structures is less than a minimum free spectral wavelength range of any resonator structure in the plurality of resonator structures. Each laser in the plurality of lasers is configured to generate continuous wave light having a respective wavelength. The laser array has a central wavelength. A variability of the central wavelength is greater than a minimum difference in resonance wavelength between any two spectrally neighboring resonator structures in the plurality of resonator structures.

A pluggable optical connector is configured to be insertable into and removable from an optical communication apparatus, and to be capable of communicating a modulation signal and a data signal with the optical communication apparatus. A wavelength-tunable light source is configured to output an output light and a local oscillation light. An optical transmission unit is configured to output an optical signal generated by modulating the output light in response to the modulation signal. An optical reception unit is configured to demodulate an optical signal received by using the local oscillation light to the data signal. Pluggable optical receptors are configured in such a manner that an optical fiber is insertable into and removable from the pluggable optical receptors, and configured to be capable of outputting the optical signal to the optical fiber and transferring the optical signal received thorough the optical fiber to the optical reception unit.

A fabricating process may include: producing a trench, in an encapsulated-silicon layer, in the location where a silicon-nitride core of the waveguide must be produced; then depositing a silicon-nitride layer on the encapsulated-silicon layer, the thickness of the deposited silicon-nitride layer being sufficient to completely fill the trench; then removing the silicon nitride situated outside of the trench to uncover an upper face with which the trench filled with silicon nitride is flush; then depositing a dielectric layer that covers the uncovered upper face in order to finalize the encapsulation of the silicon-nitride core and thus to obtain a mixed layer containing both the silicon and silicon-nitride cores encapsulated in dielectric.

An optical transmitter includes: a set of reflective semiconductor optical amplifiers (RSOAs) or other reflective gain media, a set of ring filters, a set of intermediate waveguides, a shared waveguide, a shared loop mirror, and an output waveguide. Each intermediate waveguide channels light from an RSOA in proximity to an associated ring filter to cause optically coupled light to circulate in the associated ring filter. The shared waveguide is coupled to the shared loop mirror, and is located in proximity to the set of ring filters, so that light circulating in each ring filter causes optically coupled light to flow in the shared waveguide. Each RSOA forms a lasing cavity with the shared loop reflector, wherein each lasing cavity has a different wavelength associated with a resonance of its associated ring filter. The output waveguide is optically coupled to the shared loop mirror and includes an electro-optical modulator.

A multi-channel laser source, including: a bus waveguide coupled, at an output end of the bus waveguide, to an output of the multi-channel laser source; a first semiconductor optical amplifier; a first back mirror; a first wavelength-dependent coupler, having a first resonant wavelength, on the bus waveguide; a second semiconductor optical amplifier; a second back mirror; and a second wavelength-dependent coupler, on the bus waveguide, having a second resonant wavelength, different from the first resonant wavelength. In some embodiments the first semiconductor optical amplifier is coupled to the bus waveguide by the first wavelength-dependent coupler, which is nearer to the output end of the bus waveguide than the second wavelength-dependent coupler, the second semiconductor optical amplifier is coupled to the bus waveguide by the second wavelength-dependent coupler, and the first wavelength-dependent coupler is configured to transmit light, at the second resonant wavelength, along the bus waveguide.

A tunable laser for tuning a lasing mode based on light beams travelling through at least one block of channel waveguides with at least two tunable combs, includes: a frequency selective optical multiplexer comprising a first terminal for receiving/transmitting light, at least one block of channel waveguides, each channel waveguide having a reflectively coated first tail and a second tail, and an optical coupling element optically coupling the first terminal with the second tails of the channel waveguides of the at least one block of channel waveguides, each of the channel waveguides having a different length; a gain element generating a broad spectrum of light, the gain element coupling the first terminal of the frequency selective optical multiplexer with a reflective element.

A laser comprising: at least one wavelength selective reflector that comprises a waveguide vertically coupled to at least one photonic crystal resonator, the waveguide and photonic crystal resonator being arranged to provide wave-vector matching between at least one mode of the photonic crystal resonator and at least one mode of the waveguide; an optical gain medium for generating light for coupling into the waveguide, and a reflector at an end of the optical gain medium, the reflector and the photonic crystal resonator defining a laser cavity. Light generated by the optical gain medium is coupled into the waveguide and coupled into the photonic crystal resonator, and partially reflected back to the optical gain medium.