Abstract: A system is disclosed capable of automatic and remote identification, tracking, sensing, and characterization of physical entities (objects and subjects) using structural-color tags. Optical encoding is performed in the spectral domain using photonic engineering. Several embodiments are provided for the imaging, tagging and processing aspects of the system.

Abstract: A system is disclosed capable of automatic and remote identification, tracking, sensing, and characterization of physical entities (objects and subjects) using structural-color tags. Optical encoding is performed in the spectral domain by means of photonic engineering. Several embodiments are provided for the imaging, tagging and processing aspects of the system.

Abstract: A quantum well intermixing (QWI) technique for modifying an energy bandgap during the formation of optical semi-conductor devices enables spatial control of the QWI process so as to achieve differing bandgap shifts across a wafer, device or substrate surface.

Abstract: A quantum well intermixing (QWI) technique for modifying an energy bandgap during the formation of optical semiconductor devices differing bandgap shifts across a wafer, device or substrate surface. The method includes: pattering the surface of a semiconductor substrate with QWI-initiating material in first regions of the surface; conducting a first thermal processing cycle on the substrate to generate a first bandgap shifts in the first regions; pattering the surface of the substrate with QWI initiating material in second regions of the surface, distinct from said first regions; and conducting a second thermal processing cycle on the substrate to generate a second bandgap shift in the second regions, and to generate a cumulative bandgap shift in the first regions, the cumulative bandgap shift being the cumulative result of said first and second thermal processing cycles. Further steps can produce additonal cumulative bandgap shifts.

Abstract: Photonic crystal material is used to couple two or more cavities of an optical device to provide tuneable laser output. The monolithically integrated optical device includes: a first optical cavity having a first optical axis and supporting first optical modes; a second optical cavity having a second optical axis and second, different, optical modes than the first optical cavity, the first and second optical cavities being laterally offset from one another and at least partially separated by a photonic crystal material in which the dielectric function of the material exhibits a periodic variation as a function of linear distance through the material, such that optical coupling between the first and second cavities is achieved through the photonic crystal. Multiple cavities can also be integrated in a similar fashion.