Abstract: A nanowire switching device and method. The device has a nanowire structure comprising an elongated member having a cross-sectional area ranging from about 1 nanometers but less than about 500 nanometers, but can also be at other dimensions, which vary or are substantially constant or any combination of these. The device also has a first terminal coupled to a first portion of the nanowire structure; and a second terminal coupled to a second portion of the nanowire structure. The second portion of the nanowire structure is disposed spatially from the first portion of the nanowire structure. An active surface structure is coupled to the nanowire structure. The active surface structure extends from the first portion to the second portion along the elongated member.

Abstract: Nanoribbons and nanowires having diameters less than the wavelength of light are used in the formation and operation of optical circuits and devices. Such nanostructures function as subwavelength optical waveguides which form a fundamental building block for optical integration. The extraordinary length, flexibility and strength of these structures enable their manipulation on surfaces, including the precise positioning and optical linking of nanoribbon/wire waveguides and other nanoribbon/wire elements to form optical networks and devices. In addition, such structures provide for waveguiding in liquids, enabling them to further be used in other applications such as optical probes and sensors.

Abstract: Methods of fabricating uniform nanotubes are described in which nanotubes were synthesized as sheaths over nanowire templates, such as using a chemical vapor deposition process. For example, single-crystalline zinc oxide (ZnO) nanowires are utilized as templates over which gallium nitride (GaN) is epitaxially grown. The ZnO templates are then removed, such as by thermal reduction and evaporation. The completed single-crystalline GaN nanotubes preferably have inner diameters ranging from 30 nm to 200 nm, and wall thicknesses between 5 and 50 nm. Transmission electron microscopy studies show that the resultant nanotubes are single-crystalline with a wurtzite structure, and are oriented along the <001> direction. The present invention exemplifies single-crystalline nanotubes of materials with a non-layered crystal structure. Similar “epitaxial-casting” approaches could be used to produce arrays and single-crystalline nanotubes of other solid materials and semiconductors.

Abstract: Mesoscopically ordered, hydrothermally stable metal oxide-block copolymer composite or mesoporous materials are described herein that are formed by using amphiphilic block polymers which act as structure directing agents for the metal oxide in a self-assembling system.

Abstract: A low-cost, efficient method of preparing hierarchically ordered structures by filling a minimold with a microsphere-containing latex suspension, forming an close-packed array of microspheres within the minimold and filling void space in the array with a self-assembling mixture of hydrolyzed inorganic species and amphiphilic block copolymers. A macroporous and mesoporous material can be produced by subsequent thermal removal of the microspheres and copolymers.

Abstract: A nanowire switching device and method. The device has a nanowire structure comprising an elongated member having a cross-sectional area ranging from about 1 nanometers but less than about 500 nanometers, but can also be at other dimensions, which vary or are substantially constant or any combination of these. The device also has a first terminal coupled to a first portion of the nanowire structure; and a second terminal coupled to a second portion of the nanowire structure. The second portion of the nanowire structure is disposed spatially from the first portion of the nanowire structure. An active surface structure is coupled to the nanowire structure. The active surface structure extends from the first portion to the second portion along the elongated member.

Abstract: One-dimensional nanostructures having uniform diameters of less than approximately 200 nm. These inventive nanostructures, which we refer to as “nanowires”, include single-crystalline homostructures as well as heterostructures of at least two single-crystalline materials having different chemical compositions. Because single-crystalline materials are used to form the heterostructure, the resultant heterostructure will be single-crystalline as well. The nanowire heterostructures are generally based on a semiconducting wire wherein the doping and composition are controlled in either the longitudinal or radial directions, or in both directions, to yield a wire that comprises different materials. Examples of resulting nanowire heterostructures include a longitudinal heterostructure nanowire (LOHN) and a coaxial heterostructure nanowire (COHN).

Abstract: A method for preparing transparent mesostructured inorganic/block-copolymer composites or inorganic porous solids containing optically responsive species with selective optical, optoelectronic, and sensing properties resulting therefrom. Mesoscopically organized inorganic/block copolymer composites doped with dyes or complexes are prepared for use as optical hosts, chemical/physical/biological sensors, photochromic materials, optical waveguides, tunable solid-state lasers, or optoelectronic devices. The materials can be processed into a variety of different shapes, such as films, fibers, monoliths, for novel optical and sensing applications.

Abstract: One-dimensional nanostructures having uniform diameters of less than approximately 200 nm. These inventive nanostructures, which we refer to as “nanowires”, include single-crystalline homostructures as well as heterostructures of at least two single-crystalline materials having different chemical compositions. Because single-crystalline materials are used to form the heterostructure, the resultant heterostructure will be single-crystalline as well. The nanowire heterostructures are generally based on a semiconducting wire wherein the doping and composition are controlled in either the longitudinal or radial directions, or in both directions, to yield a wire that comprises different materials. Examples of resulting nanowire heterostructures include a longitudinal heterostructure nanowire (LOHN) and a coaxial heterostructure nanowire (COHN).

Abstract: One-dimensional nanostructures having uniform diameters of less than approximately 200 nm. These inventive nanostructures, which we refer to as “nanowires”, include single-crystalline homostructures as well as heterostructures of at least two single-crystalline materials having different chemical compositions. Because single-crystalline materials are used to form the heterostructure, the resultant heterostructure will be single-crystalline as well. The nanowire heterostructures are generally based on a semiconducting wire wherein the doping and composition are controlled in either the longitudinal or radial directions, or in both directions, to yield a wire that comprises different materials. Examples of resulting nanowire heterostructures include a longitudinal heterostructure nanowire (LOHN) and a coaxial heterostructure nanowire (COHN).

Abstract: A nanowire switching device and method. The device has a nanowire structure comprising an elongated member having a cross-sectional area ranging from about 1 nanometers but less than about 500 nanometers, but can also be at other dimensions, which vary or are substantially constant or any combination of these. The device also has a first terminal coupled to a first portion of the nanowire structure; and a second terminal coupled to a second portion of the nanowire structure. The second portion of the nanowire structure is disposed spatially from the first portion of the nanowire structure. An active surface structure is coupled to the nanowire structure. The active surface structure extends from the first portion to the second portion along the elongated member.

Abstract: Homogeneous and dense arrays of nanowires are described. The nanowires can be formed in solution and can have average diameters of 40-300 nm and lengths of 1-3 ?m. They can be formed on any suitable substrate. Photovoltaic devices are also described.

Abstract: Fluidic nanotube devices are described in which a hydrophilic, non-carbon nanotube, has its ends fluidly coupled to reservoirs. Source and drain contacts are connected to opposing ends of the nanotube, or within each reservoir near the opening of the nanotube. The passage of molecular species can be sensed by measuring current flow (source-drain, ionic, or combination). The tube interior can be functionalized by joining binding molecules so that different molecular species can be sensed by detecting current changes. The nanotube may be a semiconductor, wherein a tubular transistor is formed. A gate electrode can be attached between source and drain to control current flow and ionic flow. By way of example an electrophoretic array embodiment is described, integrating MEMs switches.

Abstract: Methods of fabricating uniform nanotubes are described in which nanotubes were synthesized as sheaths over nanowire templates, such as using a chemical vapor deposition process. For example, single-crystalline zinc oxide (ZnO) nanowires are utilized as templates over which gallium nitride (GaN) is epitaxially grown. The ZnO templates are then removed, such as by thermal reduction and evaporation. The completed single-crystalline GaN nanotubes preferably have inner diameters ranging from 30 nm to 200 nm, and wall thicknesses between 5 and 50 nm. Transmission electron microscopy studies show that the resultant nanotubes are single-crystalline with a wurtzite structure, and are oriented along the <001> direction. The present invention exemplifies single-crystalline nanotubes of materials with a non-layered crystal structure. Similar “epitaxial-casting” approaches could be used to produce arrays and single-crystalline nanotubes of other solid materials and semiconductors.

Abstract: A two-layer nanotape that includes a nanoribbon substrate and an oxide that is epitaxially deposited on a flat surface of the nanoribbon substrate is described. A method for making the nanotape that includes providing plural substrates and placing the substrates in a quartz tube is also described. The oxide is deposited on the substrate using a pulsed laser ablation deposition process. The nanoribbons can be made from materials such as SnO2, ZnO, MgO, Al2O3, Si, GaN, or CdS. Also, the sintered oxide target can be made from materials such as TiO2, transition metal doped TiO2 (e.g., CO0.05Ti0.95O2), BaTiO3, ZnO, transition metal doped ZnO (e.g., Mn0.1Zn0.9O and Ni0.1Zn0.9O), LaMnO3, BaTiO3, PbTiO3, YBa2Cu3Oz, or SrCu2O2 and other p-type oxides. Additionally, temperature sensitive nanoribbon/metal bilayers and their method of fabrication by thermal evaporation are described. Metals such as Cu, Au, Ti, Al, Pt, Ni and others can be deposited on top of the nanoribbon surface.

Abstract: A low-cost, efficient method of preparing hierarchically ordered structures by filling a mold with a self-assembling mixture of hydrolyzed inorganic species and amphiphilic block copolymers and applying pressure to the mixture. Polymerization of the inorganic species within the mixture results in a mesoscopically structured material having molded features. A mesoporous material can be produced by subsequent thermal removal of the copolymers.

Abstract: Mesoscopically ordered, hydrothermally stable metal oxide-block copolymer composite or mesoporous materials are described herein that are formed by using amphiphilic block polymers which act as structure directing agents for the metal oxide in a self-assembling system.

Abstract: A low-cost, efficient method of preparing hierarchically ordered structures by combining, concurrently or sequentially, micromolding, latex templating, and cooperative self-assembly of hydrolyzed inorganic species and amphiphilic block copolymers.

Abstract: Mesoscopically ordered, hydrothermally stable metal oxide-block copolymer composite or mesoporous materials are described herein that are formed by using amphiphilic block copolymers which act as structure directing agents for the metal oxide in a self-assembling system.

Abstract: A nanowire switching device and method. The device has a nanowire structure comprising an elongated member having a cross-sectional area ranging from about 1 nanometers but less than about 500 nanometers, but can also be at other dimensions, which vary or are substantially constant or any combination of these. The device also has a first terminal coupled to a first portion of the nanowire structure; and a second terminal coupled to a second portion of the nanowire structure. The second portion of the nanowire structure is disposed spatially from the first portion of the nanowire structure. An active surface structure is coupled to the nanowire structure. The active surface structure extends from the first portion to the second portion along the elongated member.