Abstract: One example of the present invention is a nanoscale electronic device comprising a first conductive electrode, a second conductive electrode, and an anisotropic dielectric material layered between the first and second electrodes having a permittivity in a direction approximately that of the shortest distance between the first and second electrodes less than the permittivity in other directions within the anisotropic dielectric material. Additional examples of the present invention include integrated circuits that contain multiple nanoscale electronic devices that each includes an anisotropic dielectric material layered between first and second electrodes having a permittivity in a direction approximately that of the shortest distance between the first and second electrodes less than the permittivity in other directions within the anisotropic dielectric material.

Abstract: Various embodiments of the present invention are directed to sensor networks and to methods for fabricating sensor networks. In one aspect, a sensor network includes a processing node (110, 310), and one or more sensor lines (102,202,302) optically coupled to the processing node. Each sensor line comprises a waveguide (116,216,316), and one or more sensor nodes (112,210). Each sensor node is optically coupled to the waveguide and configured to measure one or more physical conditions and, encode measurement results in one or more wavelengths of light carried by the waveguide to the processing node.

Abstract: A memristor includes a substrate having a plurality of protrusions, wherein each of the plurality of protrusions extends in a first direction, a first electrode provided over at least one of the plurality of protrusions, wherein the first electrode conforms to the shape of the at least one protrusion such that the first electrode has a crest, a switching material positioned upon the first electrode; and a second electrode positioned upon the switching material such that a portion of the second electrode is substantially in line with the crest of the first electrode along the first direction, wherein an active region in the switching material is operable to be formed between the crest of the first electrode and the portion of the second electrode that is substantially in line with the crest of the first electrode.

Abstract: Various embodiments of the present invention are directed to scrambling-descrambling systems for encrypting and decrypting electromagnetic signals transmitted in optical and wireless networks. In one aspect, a system (1302) for scrambling electromagnetic signals comprises a first electronically reconfigurable electro-optical material (1402) positioned to receive a beam of electromagnetic radiation including one or more electromagnetic signals encoding data. The beam is transmitted through the electro-optical material (1402) and a two-dimensional speckled pattern (1410) is introduced into the cross-section of the beam such that data encoded in the one or more electromagnetic signals is scrambled.

Abstract: An apparatus for detecting at least one species using Raman light detection includes at least one laser source for illuminating a sample containing the at least one species. The apparatus also includes a modulating element for modulating a spatial relationship between the sample and the light beams to cause relative positions of the sample and the light beams to be oscillated, in which Raman light at differing intensity levels are configured to be emitted from the at least one species based upon the different wavelengths of the light beams illuminating the sample. The apparatus also includes a Raman light detector and a post-signal processing unit configured to detect the at least one species.

Abstract: An electromagnetic wave receiving antenna includes a spiral element configured to selectively attenuate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths, and to concentrate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths other than the attenuated wavelengths.

Abstract: An electromagnetic wave receiving antenna includes a spiral element configured to selectively attenuate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths, and to concentrate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths other than the attenuated wavelengths.

Abstract: A flexible graphene-based metamaterial structure is disclosed that can operate at above liquid helium or liquid nitrogen temperatures, up to room temperature or above in applications similar to those for which a superconductor-based material structure is used. The flexible graphene-based metamaterial structure is formed from a flexible substrate, and a plurality of two-dimensional graphene blocks disposed in an array on the flexible substrate, each graphene block having a plurality of graphene sheets. The lateral dimension of the face of the graphene blocks is dependent on the temperature of operation of the flexible metamaterial structure. The flexible graphene-based metamaterial structure can be used for cloaking, with application in magnetic shielding.

Abstract: A vibrating tip surface enhanced Raman spectroscopy (SERS) apparatus, system and method employ a nano-needle configured to vibrate. The apparatus includes the nano-needle with a substantially sharp tip at a free end opposite an end attached to a substrate. The tip is configured to adsorb an analyte. The apparatus further includes a vibration source configured to provide an alternating current (AC) electric field that induces a vibration of the free end and the tip of the nano-needle. Vibration of the nano-needle under the influence of the AC electric field facilitates detection of a Raman scattering signal from the analyte adsorbed on the nano-needle tip. The system further includes a synchronous detector configured to be gated cooperatively with the vibration of the nano-needle. The method includes inducing the vibration, illuminating the vibrating tip to produce a Raman signal, and detecting the Raman signal using the detector.

Abstract: A light amplifying structure 100 for Raman spectroscopy includes a a resonant cavity 108. A distance between a first portion 102B and a second portion 102A of the structure 100 forming the resonant cavity 108 is used to amplify excitation light emitted from a light source 420 into the resonant cavity 108 at a first resonant frequency of the resonant cavity 108. Also, the resonant cavity 108 amplifies radiated light radiated from a predetermined molecule excited by the excitation light in the resonant cavity at a second resonant frequency of the resonant cavity 108.

Abstract: A thermistor includes a multi-layer graphite structure having a basal plane resistivity that increases with increasing temperature; a substrate upon which the graphite structure is mounted; current and voltage electrodes attached to the graphite structure; current and voltage wiring; and a voltage measuring device to measure voltage out when current is applied to the thermistor.

Abstract: An apparatus for phase detection of Raman scattered light emitted from a sample includes a first polarizer positioned along a first optical path containing a first beam and a second polarizer positioned along a second optical path containing a second beam. The first polarizer and second polarizer polarize the first beam and the second beam in one of mutually perpendicular and mutually parallel first and second directions. The apparatus also includes an optical phase modulator positioned along the second optical path to controllably modulate a phase of the second beam, a beam splitter positioned to join the first beam and the second beam together, and a spectrometer to receive the joined first beam and second beam and to measure a phase shift of the first beam and the second beam.

Abstract: A reconfigurable surface enhanced Raman spectroscopy (SERS) apparatus, system and method employ a stimulus responsive material to move nanorods of a plurality between inactive and active configurations. The apparatus includes the plurality of nanorods and the stimulus responsive material. The system further includes a Raman signal detector. The method of reconfigurable SERS includes providing the plurality of nanorods and exposing the stimulus responsive material to a stimulus. The exposure causes a change in one or more of a size, a shape and a volume of the stimulus responsive material that moves the nanorods between the inactive and active configurations. The active configuration facilitates one or both of production and detection of a Raman scattering signal emitted by the analyte.

Abstract: A signal-amplification device for surface enhanced Raman spectroscopy (SERS). The signal-amplification device includes a non-SERS-active (NSA) substrate, a plurality of multi-tiered non-SERS-active nanowire (MNSANW) structures and a plurality of metallic SERS-active nanoparticles. In addition, a MNSANW structure of the plurality of MNSANW structures includes a main arm of a plurality of main arms and a plurality of arms of at least secondary order. The plurality of main arms is disposed on the NSA substrate; and, a secondary arm of the plurality of arms is disposed on the main arm. Moreover, a metallic SERS-active nanoparticle of the plurality of metallic SERS-active nanoparticles is disposed on a surface of the MNSANW structure.

Abstract: A silicon-germanium, quantum-well, light-emitting diode (120). The light-emitting diode (120) includes a p-doped portion (410), a quantum-well portion (420), and an p-doped portion (430). The quantum-well portion (420) is disposed between the p-doped portion (410) and the n-doped portion (430). The quantum-well portion (420) includes a carrier confinement region that is configured to facilitate luminescence with emission of light (344) produced by direct recombination (340) of an electron (314) with a hole (324) confined within the carrier confinement region. The p-doped portion (410) includes a first alloy of silicon-germanium, and the n-doped portion (430) includes a second alloy of silicon-germanium.

Abstract: An apparatus for detecting at least one molecule using Raman light detection includes a substrate for supporting a sample containing the at least one molecule, a laser source for emitting a laser beam to cause Raman light emission from the at least one molecule, a modulating element for modulating a spatial relationship between the laser beam and the substrate at an identified frequency to cause the Raman light to be emitted from the at least one molecule at the identified frequency, at least one detector for detecting the Raman light emitted from the at least one molecule, and a post-signal processing unit configured to process the detected Raman light emission at the identified frequency to detect the at least one molecule.

Abstract: A memristor includes a first electrode having a first surface, at least one electrically conductive nanostructure provided on the first surface, in which the at least one electrically conductive nanostructure is relatively smaller than a width of the first electrode, a switching material positioned upon said first surface, in which the switching material covers the at least one electrically conductive nanostructure, and a second electrode positioned upon the switching material substantially in line with the at least one electrically conductive nanostructure, in which an active region in the switching material is formed substantially between the at least one electrically conductive nanostructure and the first electrode.

Abstract: Various embodiments of the present invention are directed to external, electronically controllable modulators. In one embodiment, a modulating device (100,400) includes a first electrode (104,404), a second electrode (106,406), and an active region (102,402). The active region is configured so that at least a portion of the active region is disposed between the first electrode and the second electrode. Applying a voltage of an appropriate magnitude and polarity to the electrodes changes the conductivity of the active region which in turn shifts the phase and/or amplitude of electromagnetic radiation transmitted through the active region.

Abstract: An active chiral photonic metamaterial having a dynamically controllable photonic material parameter is employed in a system and a method of polarization rotation. The active chiral photonic metamaterial includes a first chiral photonic element formed in a first metal layer, a second chiral photonic element formed in a second metal layer, and an active material layer disposed between the first and second metal layers. The active material layer includes the photonic material parameter that is dynamically controllable. A coupling between the first chiral photonic element and the second chiral photonic element is a function of the photonic material parameter of the active material layer. The system further includes a means for controlling the dynamically controllable photonic material parameter. The method includes illuminating the active chiral photonic metamaterial with an optical signal and applying a control signal to vary the dynamically controllable photonic material parameter.

Abstract: Embodiments of the present invention are directed to nanoscale memristor devices that provide nonvolatile memristive switching. In one embodiment, a memristor device (100) comprises an active region (102), a first electrode (104) disposed on a first surface of the active region, and a second electrode (106) disposed on a second surface of the active region, the second surface opposite the first surface. The first electrode is configured with a larger width than the active region in a first direction, and the second electrode is configured with a larger width than the active region in a second direction. Application of a voltage to at least one of the electrodes produces an electric field across a sub-region (108) within the active region between the first electrode and the second electrode.