Abstract: According to various embodiments, there is provided an optical device including a first waveguide configured to guide a light wave along a longitudinal axis; a first grating at least partially formed in the first waveguide, the first grating arranged away from the longitudinal axis in a first direction; and a second grating at least partially formed in the first waveguide, the second grating arranged away from the longitudinal axis in a second direction; wherein the second direction is different from the first direction.

Abstract: There is provided an integrated laser. The integrated laser includes a semiconductor waveguide having a first section, a second section and a third section. The integrated laser further includes an active region formed on the third section of the semiconductor waveguide, the active region configured for generating light, and a coupler formed on the second section of the semiconductor waveguide, the coupler configured for coupling said light between the semiconductor waveguide and the active region. In particular, the first section comprises a multi-branch splitter having a ring structure formed between two branches of the multi-branch splitter for emission wavelength control of the integrated laser. Preferably, the multi-branch splitter is a Y-branch splitter and the ring structure is formed in a space between two branches of the Y-branch splitter. There is also provided a method of fabrication thereof, an integrated tunable laser and an integrated tunable laser system.

Abstract: There is provided an integrated laser. The integrated laser includes a semiconductor waveguide having a first section, a second section and a third section. The integrated laser further includes an active region formed on the third section of the semiconductor waveguide, the active region configured for generating light, and a coupler formed on the second section of the semiconductor waveguide, the coupler configured for coupling said light between the semiconductor waveguide and the active region. In particular, the first section comprises a multi-branch splitter having a ring structure formed between two branches of the multi-branch splitter for emission wavelength control of the integrated laser. Preferably, the multi-branch splitter is a Y-branch splitter and the ring structure is formed in a space between two branches of the Y-branch splitter. There is also provided a method of fabrication thereof, an integrated tunable laser and an integrated tunable laser system.

Abstract: Methods and systems to generate derivative information sources, from original information sources, use an ontology that provides a logic-based representation formalism of each of a number of original information sources, the original information sources having heterogeneous representation formalisms. The original information sources are transformed to the ontology. A number of derivative information sources, corresponding to the original information sources, may be automatically generated from the ontology.