Abstract: A self-aligned fabrication process for aligning photonic waveguide layers of a 3D photonic structure such that light may be efficiently transferred between the two layers is described. The self-aligned fabrication process comprises using a mask to pattern both photonic waveguide layers, such that they are aligned three-dimensionally via a single lithographic processing step, and thus fabricating a photonically coupled region of the 3D photonic structure. Selective etching may also be used to taper a given photonic waveguide layer for adiabatic coupling, and/or to produce other non-trivial geometric shapes in the photonic waveguide layers. Such 3D photonic structures may be fabricated for use in quantum memory devices, in which one of the photonic waveguide layers may host quantum memories and another photonic waveguide layer may interface with an optical fiber, such that light may be transferred between an optical fiber and respective ones of the quantum memories.

Abstract: System and methods for aligning optical elements to form adiabatic couplings are disclosed. An alignment device includes a common platform and a plurality of electrically-controlled mounts affixed to the common platform. Individual fibers of a first set of fibers that are to be aligned with a second set of fibers are coupled into respective ones of the plurality of electrically-controlled mounts. The platform as a whole is positioned in 3D space to align the first set of fibers with the second set of fibers, within a threshold level of alignment. Then, individual ones of the electrically-controlled mounts are adjusted to further align respective fibers of the first set of fibers with a corresponding fiber of the second set. In some embodiments, scattered light and/or signal strength are used as feedback measurements to guide the alignment process.

Abstract: Systems and methods for securing optical fibers with complimentary tapered ends are described. In some embodiments, optical fibers are aligned to form an adiabatic coupling, and a first one of the optical fibers is secured, via an adhesive, to a structure of an optical device hosting a second one of the optical fibers with which the first optical fibers is coupled. The first and second optical fibers, coupled and secured using the adhesive, are then immersed in a photo-active liquid polymer and two-photon lithography is used to form an additional securing structure around the adiabatically coupled ends of the first and second optical fibers. The additional securing structure is configured to maintain the adiabatic coupling throughout various mechanical and/or thermal shocks the adiabatically coupled fibers may encounter.

Abstract: A thin film organic photovoltaic device or solar cell in one embodiment includes an organic active bilayer and an ultrathin two-dimensional metallic nanogrid as a transparent conducting electrode which receives incident light. The nanogrid excites surface plasmonic resonances at an interface between the nanogrid and active bilayer from the incident light to enhance photon absorption in the active bilayer below the nanogrid. In another embodiment, spatially separated nanograting electrodes may alternatively be formed by double one-dimensional nanogratings disposed on opposite sides of the organic active bilayer. The spatially separated nanogratings may be oriented perpendicular to each other.

Abstract: A thin film organic photovoltaic device or solar cell in one embodiment includes an organic active bilayer and an ultrathin two-dimensional metallic nanogrid as a transparent conducting electrode which receives incident light. The nanogrid excites surface plasmonic resonances at an interface between the nanogrid and active bilayer from the incident light to enhance photon absorption in the active bilayer below the nanogrid. In another embodiment, spatially separated nanograting electrodes may alternatively be formed by double one-dimensional nanogratings disposed on opposite sides of the organic active bilayer. The spatially separated nanogratings may be oriented perpendicular to each other.

Abstract: An ultrathin plasmonic subtractive color filter in one embodiment includes a transparent substrate and an ultrathin nano-patterned film formed on the substrate. A plurality of elongated parallel nanoslits is formed through the film defining a nanograting. The nanoslits may be spaced apart at a pitch selected to transmit a wavelength of light. The film is formed of a material having a thickness selected, such that when illuminated by incident light, surface plasmon resonances are excited at top and bottom surfaces of the film which interact and couple to form hybrid plasmon modes. The film changes between colored and transparent states when alternatingly illuminated with TM-polarized light or TE-polarized light, respectively. In one configuration, an array of nanogratings may be disposed on the substrate to form a transparent display system.