Abstract: A superlens for controlling the size and the phase of an electromagnetic beam that passes through it, and a method for independently controlling the horizontal and vertical focusing of the electromagnetic beam using the superlens is provided. The superlens comprises a vertically GRIN multi-layer structure with one or more horizontally curved sidewalls. The vertical focusing is controlled by varying the longitudinal thickness of the multi-layer structure. The horizontal focusing is controlled by varying the profile and the radius of curvature of the horizontally curved sidewalls. Varying the thickness and radius of curvature is done by etching. Also provided is a method for making the superlens.

Abstract: An optical medium has a graded effective refractive index with a high maximum refractive index change. The medium is formed using alternating layers of two or more materials having significantly different refractive indices. The thickness of the layers of at least one of the materials is substantially less than the effective light wavelength of interest. The effective index of refraction in a local region within the medium depends on the ratio of the average volumes of the two materials in the local region. A graded index of refraction is provided by varying the relative thicknesses of the two materials.

Abstract: An optical medium has a graded effective refractive index with a high maximum refractive index change. The medium is formed using alternating layers of two or more materials having significantly different refractive indices. The thickness of the layers of at least one of the materials is substantially less than the effective light wavelength of interest. The effective index of refraction in a local region within the medium depends on the ratio of the average volumes of the two materials in the local region. A graded index of refraction is provided by varying the relative thicknesses of the two materials.

Abstract: An optical medium has a graded effective refractive index with a high maximum refractive index change. The medium is formed using alternating layers of two or more materials having significantly different refractive indices. The thickness of the layers of at least one of the materials is substantially less than the effective light wavelength of interest. The effective index of refraction in a local region within the medium depends on the ratio of the average volumes of the two materials in the local region. A graded index of refraction is provided by varying the relative thicknesses of the two materials.

Abstract: Optical modules and methods for making optical modules are described. In one embodiment, an optical module includes a substrate assembly including a photonic chip mounting region, and a groove extending towards the photonic chip mounting region. A waveguide is disposed within the groove. A plurality of spacers is on the chip mounting region, each spacer having a predetermined height. A photonic chip is placed on the plurality of spacers and above the chip mounting region, and an optical coupler is between the photonic chip and the waveguide.

Abstract: A process for shifting the bandgap energy of a quantum well layer (e.g., a III-V semiconductor quantum well layer) without inducing complex crystal defects or generating significant free carriers. The process includes introducing ions into a quantum well structure at an elevated temperature, for example, in the range of from about 200° C. to about 700° C. The quantum well structure that has had ions introduced therein includes upper and lower barrier layers with quantum well layers therebetween. The quantum well structure is then pre-annealed at a temperature and time that does not induce quantum well intermixing, but does diffuse the point defects closer to the quantum well layer. Finally, the structure is thermally annealed at a higher temperature to induce quantum well intermixing (QWI) in the quantum well structure, which shifts the bandgap energy of the quantum well layer.

Abstract: A coupling system for photonic integrated circuits and integrated optical waveguides is provided. A recess is formed in a substrate on which one or more integrated optical waveguides are disposed, the recess being located at the desired mounting location of the photonic integrated circuit. At least one end wall of the recess is inclined with respect to a normal to the substrate surface. At least one end face of a photonic integrated circuit is inclined to match the inclined end wall of the recess. The length, width, and depth of the recess are controlled so that inserting the photonic integrated circuit into the recess passively provides both lateral and vertical alignment of the photonic integrated circuit with the integrated optical waveguide(s).

Abstract: In a connection between an optical fiber or optical fiber array and an integrated optical waveguide or integrated optical waveguide array mounted or fabricated on a grooved substrate, an end face of an optical fiber array has a first facet and a second facet. The first facet has an inclination angle substantially equal to the inclination angle of an end wall of the substrate groove; the second facet has an inclination angle substantially equal to the inclination angle of the end face of the integrated optical waveguide. When the optical fiber array is mounted on the grooved substrate, each of the fibers rests in one of the substrate grooves. The first facet of each optical fiber end face is aligned with the end wall of the groove in which it rests, and the second facet is aligned with the end face of the integrated optical waveguide.

Abstract: A process for shifting the bandgap energy of a quantum well layer (e.g., a III-V semiconductor quantum well layer) without inducing complex crystal defects or generating significant free carriers. The process includes introducing ions into a quantum well structure at an elevated temperature, for example, in the range of from about 200° C. to about 700° C. The quantum well structure that has had ions introduced therein includes upper and lower barrier layers with quantum well layers therebetween. The quantum well structure is then pre-annealed at a temperature and time that does not induce quantum well intermixing, but does diffuse the point defects closer to the quantum well layer. Finally, the structure is thermally annealed at a higher temperature to induce quantum well intermixing (QWI) in the quantum well structure, which shifts the bandgap energy of the quantum well layer.

Abstract: Optical modules and methods for making optical modules are described. In one embodiment, an optical module includes a substrate assembly including a photonic chip mounting region, and a groove extending towards the photonic chip mounting region. A waveguide is disposed within the groove. A plurality of spacers is on the chip mounting region, each spacer having a predetermined height. A photonic chip is placed on the plurality of spacers and above the chip mounting region, and an optical coupler is between the photonic chip and the waveguide.

Abstract: Composite optical waveguide structures or mode transformers and their methods of fabrication and integration are disclosed, wherein the structures or mode transformers are capable of bi-directional light beam transformation between a small mode size waveguide and a large mode size wavguide. One aspect of the present invention is directed to an optical mode transformer comprising a waveguide core having a high refractive index contrast between the waveguide core and the cladding, the optical mode transformer being configured such that the waveguide core has a taper wherein a thickness of the waveguide core tapers down to a critical thickness value, the critical thickness value being defined as a thickness value below which a significant portion of the energy of a light beam penetrates into the cladding layers surrounding the taper structure thereby enlarging the small mode size.