Abstract: Bendable Materials for Electromagnetic Interference Shielding and Detection of Infrared and Visible Radiation

Abstract: Traveling-wave tube amplifiers and methods for making slow-wave structures for the amplifiers are provided. The SWSs include helical conductors that are self-assembled via the release of stressed electrically conductive strips from a sacrificial material. The helical conductors can be electroplated post-self-assembly to fortify the helix, reduce losses, and tailor the dimensions and operating parameters of the helix.

Abstract: Traveling-wave tube amplifiers for high-frequency signals, including terahertz signals, and methods for making a slow-wave structure for the traveling-wave tube amplifiers are provided. The slow-wave structures include helical conductors that are self-assembled via the release and relaxation of strained films from a sacrificial growth substrate.

Abstract: Traveling-wave tube amplifiers for high-frequency signals, including terahertz signals, and methods for making a slow-wave structure for the traveling-wave tube amplifiers are provided. The slow-wave structures include helical conductors that are self-assembled via the release and relaxation of strained films from a sacrificial growth substrate.

Abstract: Traveling-wave tube amplifiers and methods for making slow-wave structures for the amplifiers are provided. The SWSs include helical conductors that are self-assembled via the release of stressed electrically conductive strips from a sacrificial material. The helical conductors can be electroplated post-self-assembly to fortify the helix, reduce losses, and tailor the dimensions and operating parameters of the helix.

Abstract: Methods for fabricating thin, high-aspect-ratio Ge nanostructures from high-quality, single-crystalline Ge substrates are provided. Also provided are grating structures made using the methods. The methods utilize a thin layer of graphene between a surface of a Ge substrate, and an overlying resist layer. The graphene passivates the surface, preventing the formation of water-soluble native Ge oxides that can result in the lift-off of the resist during the development of the resist.

Abstract: Traveling-wave tube amplifiers for high-frequency signals, including terahertz signals, and methods for making a slow-wave structure for the traveling-wave tube amplifiers are provided. The slow-wave structures include helical conductors that are self-assembled via the release and relaxation of strained films from a sacrificial growth substrate.

Abstract: Methods for fabricating thin, high-aspect-ratio Ge nanostructures from high-quality, single-crystalline Ge substrates are provided. Also provided are grating structures made using the methods. The methods utilize a thin layer of graphene between a surface of a Ge substrate, and an overlying resist layer. The graphene passivates the surface, preventing the formation of water-soluble native Ge oxides that can result in the lift-off of the resist during the development of the resist.

Abstract: A self-assembling element fabricated using integrated circuit techniques may provide a small diameter helical conductor surrounding an electron beam for the construction of a vacuum electronic device such as a traveling-wave tube for terahertz scale signal.

Abstract: A solar cell for collecting solar radiation can include a barrier layer such as a dielectric barrier layer and a heterostructure including a first light absorbing layer and at least a second light absorbing layer. A method for forming the solar cell can include forming a sacrificial layer on a support substrate and forming the barrier layer on the sacrificial layer. The barrier layer is formed to have a strain gradient through its thickness. The heterostructure is attached to the barrier layer and the sacrificial layer is removed, thereby separating the barrier layer and the heterostructure from the support substrate. During the removal of the sacrificial layer, the strain gradient causes the barrier layer and heterostructure, to roll, curl, or spiral, thereby resulting in a radially stacked heterostructure that provides a light concentrating optical cavity having multiple light absorbing layers with different band gaps.

Abstract: A self-assembling element fabricated using integrated circuit techniques may provide a small diameter helical conductor surrounding an electron beam for the construction of a vacuum electronic device such as a traveling-wave tube for terahertz scale signal.

Abstract: A detector or sensor including a transistor having a sensor element that generates a current when exposed to a stimulus such as light or a chemical, in one implementation, the sensor element is positioned between a transistor gate and a transistor channel. When the sensor element is not being exposed to the stimulus, the transistor outputs a first voltage on a transistor drain contact when the transistor inverts. When the sensor element is being exposed to the stimulus, the transistor outputs a second voltage on the transistor drain contact when the transistor inverts, where the second voltage is higher than the first voltage.

Abstract: A solar cell for collecting solar radiation can include a barrier layer such as a dielectric barrier layer and a heterostructure including a first light absorbing layer and at least a second light absorbing layer. A method for forming the solar cell can include forming a sacrificial layer on a support substrate and forming the barrier layer on the sacrificial layer. The barrier layer is formed to have a strain gradient through its thickness. The heterostructure is attached to the barrier layer and the sacrificial layer is removed, thereby separating the barrier layer and the heterostructure from the support substrate. During the removal of the sacrificial layer, the strain gradient causes the barrier layer and heterostructure, to roll, curl, or spiral, thereby resulting in a radially stacked heterostructure that provides a light concentrating optical cavity having multiple light absorbing layers with different band gaps.

Abstract: A method for forming a semiconductor structure, includes: providing a host substrate; forming at least one sacrificial layer having two or more group-V species over the host substrate; forming at least one semiconductor layer over the at least one sacrificial layer; and transferring at least a portion of the at least one semiconductor layer from the host substrate onto an alternate substrate.

Abstract: Electrically conductive material structures, analog electronic devices incorporating the structures and methods for making the structures are provided. The structures include a layer of graphene on a semiconductor substrate. The graphene layer and the substrate are separated by an interfacial region that promotes transfer of charge carriers from the surface of the substrate to the graphene.

Abstract: Electrically conductive material structures, analog electronic devices incorporating the structures and methods for making the structures are provided. The structures include a layer of graphene on a semiconductor substrate. The graphene layer and the substrate are separated by an interfacial region that promotes transfer of charge carriers from the surface of the substrate to the graphene.

Abstract: Electronic devices for the generation of electromagnetic radiation are provided. Also provided are methods for using the devices to generate electromagnetic radiation. The radiation sources include an anisotropic electrically conducting thin film that is characterized by a periodically varying charge carrier mobility in the plane of the film. The periodic variation in carrier mobility gives rise to a spatially varying electric field, which produces electromagnetic radiation as charged particles pass through the film.

Abstract: Electronic devices for the generation of electromagnetic radiation are provided. Also provided are methods for using the devices to generate electromagnetic radiation. The radiation sources include an anisotropic electrically conducting thin film that is characterized by a periodically varying charge carrier mobility in the plane of the film. The periodic variation in carrier mobility gives rise to a spatially varying electric field, which produces electromagnetic radiation as charged particles pass through the film.

Abstract: Thin films, which are deposited on a sacrificial film on a substrate, are released and bonded back on a substrate surface. This technology provides open and closed 2D confined micro-/nano-channels and channel networks on a substrate surface. The geometry, size and complexity of the channels and channel networks can be modified by the film and substrate properties as well as the treatment techniques of the sacrificial layer etching. A method to fabricate such structures with position- and pattern-controllability is provided.

Abstract: Thin films, which are deposited on a sacrificial film on a substrate, are released and bonded back on a substrate surface. This technology provides open and closed 2D confined micro-/nano-channels and channel networks on a substrate surface. The geometry, size and complexity of the channels and channel networks can be modified by the film and substrate properties as well as the treatment techniques of the sacrificial layer etching. A method to fabricate such structures with position- and pattern-controllability is provided.