Abstract:
An apparatus for controlling propagation of incident electromagnetic radiation is described, comprising a composite material having electromagnetically reactive cells of small dimension relative to a wavelength of the incident electromagnetic radiation. At least one of a capacitive and inductive property of at least one of the electromagnetically reactive cells is temporally controllable to allow temporal control of an associated effective refractive index encountered by the incident electromagnetic radiation while propagating through the composite material.
Abstract:
An imprinting apparatus and method of fabrication provide a mold having a pattern for imprinting. The apparatus includes a semiconductor substrate polished in a [110] direction. The semiconductor substrate has a (110) horizontal planar surface and vertical sidewalls of a wet chemical etched trench. The sidewalls are aligned with and therefore are (111) vertical lattice planes of the semiconductor substrate. The semiconductor substrate includes a plurality of vertical structures between the sidewalls, wherein the vertical structures may be nano-scale spaced apart. The method includes wet etching a trench with spaced apart (111) vertical sidewalls in an exposed portion of the (110) horizontal surface of the semiconductor substrate along (111) vertical lattice planes. A chemical etching solution is used that etches the (111) vertical lattice planes slower than the (110) horizontal lattice plane. The method further includes forming the imprinting mold.
Abstract:
A nanoimprint mold is described, comprising a plurality of alternating layers of distinct materials differentially etched along an edge thereof, said layers having spatially varying thicknesses along said edge such that nanolines patterned with said nanoimprint mold have corresponding spatially varying pitches.
Abstract:
An apparatus for sensing at least one property of a fluid is described. A first photonic crystal structure and a second photonic crystal structure are defined in a dielectric slab. The first and second photonic crystal structures comprise differently patterned arrays of channels extending through the dielectric slab. The apparatus further comprises a fluid introduction device configured to introduce a common volume of the fluid into the channels of the first and second photonic crystal structures. The at least one property of the fluid can be sensed by measuring the propagation of radiation through the first and second photonic crystal structures.
Abstract:
Devices, systems, and methods for enhancing Raman spectroscopy and hyper-Raman are disclosed. A molecular analysis device for performing Raman spectroscopy comprises a substrate and a laser source disposed on the substrate. The laser source may be configured for emanating a laser radiation, which may irradiate an analyte disposed on a Raman enhancement structure. The Raman enhancement structure may be disposed in a waveguide. The molecular analysis device also includes a wavelength demultiplexer and radiation sensors disposed on the substrate and configured for receiving a Raman scattered radiation, which may be generated by the irradiation of the analyte and Raman enhancement structure.
Abstract:
A gain-clamped semiconductor optical amplifier comprises: at least one first surface; at least one second surface, each second surface facing and electrically isolated from a respective first surface; a plurality of nanowires connecting each opposing pair of the first and second surfaces in a bridging configuration; and a signal waveguide overlapping the nanowires such that an optical signal traveling along the signal waveguide is amplified by energy provided by electrical excitation of the nanowires.
Abstract:
A method for creating a nanostructure according to one embodiment includes depositing material in a template for forming an array of nanocables; removing only a portion of the template such that the template forms an insulating layer between the nanocables; and forming at least one layer over the nanocables. A nanostructure according to one embodiment includes a nanocable having a roughened outer surface and a solid core. A nanostructure according to one embodiment includes an array of nanocables each having a roughened outer surface and a solid core, the roughened outer surface including reflective cavities; and at least one layer formed over the roughened outer surfaces of the nanocables, the at least one layer creating a photovoltaically active p-n junction. Additional systems and methods are also presented.
Abstract:
A nano-scale device and method of fabrication provide a nanowire having (111) vertical sidewalls. The nano-scale device includes a semiconductor-on-insulator substrate polished in a [110] direction, the nanowire, and an electrical contact at opposite ends of the nanowire. The method includes wet etching a semiconductor layer of the semiconductor-on-insulator substrate to form the nanowire extending between a pair of islands in the semiconductor layer. The method further includes depositing an electrically conductive material on the pair of islands to form the electrical contacts. A nano-pn diode includes the nanowire as a first nano-electrode, a pn-junction vertically stacked on the nanowire, and a second nano-electrode on a (110) horizontal planar end of the pn-junction. The nano-pn diode may be fabricated in an array of the diodes on the semiconductor-on-insulator substrate.
Abstract:
A patterned array of metallic nanostructures and fabrication thereof is described. A device comprises a patterned array of metallic columns vertically extending from a substrate. Each metallic column is formed by metallically coating one of an array of non-metallic nanowires catalytically grown from the substrate upon a predetermined lateral pattern of seed points placed thereon according to a nanoimprinting process. An apparatus for fabricating a patterned array of metallic nanostructures is also described.
Abstract:
A NERS-active structure includes a deformable, active nanoparticle support structure for supporting a first nanoparticle and a second nanoparticle that is disposed proximate the first nanoparticle. The nanoparticles each comprise a NERS-active material. The deformable, active nanoparticle support structure is configured to vary the distance between the first nanoparticle and the second nanoparticle while performing NERS. Various active nanoparticle support structures are disclosed. A NERS system includes such a NERS-active structure, a radiation source for generating radiation scatterable by an analyte located proximate the NERS-active structure, and a radiation detector for detecting Raman scattered radiation scattered by the analyte. A method for performing NERS includes providing such a NERS-active structure, providing an analyte at a location proximate the NERS-active structure, irradiating the NERS-active structure and the analyte with radiation, varying the distance between the nanoparticles, and detecting Raman scattered radiation scattered by the analyte.