Abstract: Provided herein are methods and apparatus for characterizing high aspect ratio (HAR) structures of fabricated or partially fabricated semiconductor devices. The methods involve using small angle X-ray scattering (SAXS) to determine average parameters of an array of HAR structures. In some implementations, SAXS is used to analyze symmetry of HAR structures in a sample and may be referred to as tilted structural symmetry analysis-SAXS (TSSA-SAXS) or TSSA. Analysis of parameters such as tilt, sidewall angle, bowing, and the presence of multiple tilts in HAR structures may be performed.

Abstract: A sample carrier for in situ transmission electron microscopy (TEM) has a dielectric substrate with a conductive layer that forms a coplanar waveguide. The coplanar waveguide has a first and second leads formed by the conductive layer. The first lead is between an adjacent pair of second leads and is spaced from the second leads by a respective gap. The coplanar waveguide is configured to transmit an electrical signal to a specimen held by the sample carrier, in particular, an electrical signal having a frequency in the radio-frequency (RF) regime (3 kHz-300 GHz), for example, up to 100 GHz. The sample carrier may be mounted to a TEM sample holder, which supports the sample carrier within a vacuum chamber of the microscope and provides electrical connection between the leads of the sample carrier and an RF source external to the vacuum chamber.

Abstract: A nanohole array (NHA)-based plasmonic sensor (e.g., gas/condensed phase sensor), their preparation, and their use to detect and analyze samples, especially mixtures of chemicals/bio-chemicals.

Abstract: This disclosure describes systems, methods, and apparatus for multilayer superconducting structures comprising electroplated Rhenium, where the Rhenium operates in a superconducting regime at or above 4.2 K, or above 1.8 K where specific temperatures and times of annealing have occurred. The structure can include at least a first conductive layer applied to a substrate, where the Rhenium layer is electroplated to the first layer. A third layer formed from the same or a different conductor as the first layer can be formed atop the Rhenium layer.

Abstract: A method of separating and extracting carbon nanotubes, the method includes introducing the carbon nanotubes into a two-phase system that includes a first component and a second component, the first component being different from the second component. The method includes introducing a chemical agent into the two-phase system, mixing the chemical agent and the carbon nanotubes in the two-phase system, removing the first component to extract a first portion of the carbon nanotubes contained in the first component after the mixing, replenishing the two-phase system with fresh first component, and extracting a second portion of the carbon nanotubes contained in the fresh first component. A bandgap of the carbon nanotubes in the first portion is different from the bandgap of the carbon nanotubes in the second portion.

Abstract: This disclosure describes systems, methods, and apparatus for multilayer superconducting structures comprising electroplated Rhenium, where the Rhenium operates in a superconducting regime at or above 4.2 K, or above 1.8 K where specific temperatures and times of annealing have occurred. The structure can include at least a first conductive layer applied to a substrate, where the Rhenium layer is electroplated to the first layer. A third layer formed from the same or a different conductor as the first layer can be formed atop the Rhenium layer.

Abstract: Various embodiments of the present technology provide a novel architecture for optical frequency conversion in a waveguide which can be applied to any suitable nonlinear waveguide material and any wavelength. In accordance with some embodiments, phase-matched bends can be used to increase the nonlinear interaction length. For example, the device can begin with a straight waveguide section with a width designed for phase-matching. When the straight waveguide section approaches the end of the chip, a bending waveguide section allows the waveguide to meander back in the opposite direction. Various embodiments of the bend can have a wider or narrower width to eliminate phase-matching for second harmonic generation (SHG) and instead provide a 2? phase-shift between the pump and signal light. Therefore, at the end of the bend, the pump and signal light are in-phase and a phase-matched width will continue the SHG process.

Abstract: Gradient elution isotachophoretic apparatus, and systems for performing gradient elution isotachophoresis to separate, purify, concentrate, quantify, and/or extract charged analytes from a sample. The isotachophoretic apparatus include an electrophoretic assembly, a sampling assembly connected to the electrophoretic assembly, and/or a support structure connected to the electrophoretic assembly and/or to the sampling assembly. The system includes an isotachophoretic apparatus, and a controller communicatively coupled to the isotachophoretic apparatus. The controller includes a storage medium and a processor for executing computer readable and executable instructions.

Abstract: A flame retardant coating composition comprising poly(dopamine) and either tris(hydroxymethyl)aminomethane) or gaseous ammonia, as well as an article comprising a substrate and the flame retardant coating composition, is provided. In various embodiments, the poly(dopamine) is substantially water insoluble. The coating composition can further comprise at least one additional component selected from the group consisting of melamine, an anionic clay, a phosphorus-containing compound, an amine-containing compound, aluminosilicates, silicon oxides, and combinations thereof. Also provided are methods for forming the flame retardant coating composition and methods for increasing flame retardant properties of a substrate.

Abstract: Methods of fabricating micro- and nanostructures comprise top-down etching of lithographically patterned GaN layer to form an array of micro- or nanopillar structures, followed by selective growth of GaN shells over the pillar structures via selective epitaxy. Also provided are methods of forming micro- and nanodisk structures and microstructures formed from thereby.

Abstract: A cold cathode field emission electron source capable of emission at levels comparable to thermal sources is described. Emission in excess of 6 A/cm2 at 7.5 V/?m is demonstrated in a macroscopic emitter array. The emitter has a monolithic and rigid porous semiconductor nanostructure with uniformly distributed emission sites, and is fabricated through a room temperature process which allows for control of emission properties. These electron sources can be used in a wide range of applications, including microwave electronics and x-ray imaging for medicine and security.

Abstract: A method of comb-based spectroscopy for measuring a CW source at time-bandwidth limited resolution by using frequency combs with a high degree of mutual coherence (<1 radian phase noise).

Abstract: A contactless, three-dimensional fingerprint scanner apparatus, method, and system are described. The contactless fingerprint scanner can provide either, or both, topographical contrast of three-dimensional fingerprint features and optical contrast of a three-dimensional fingerprint surface. Data captured from scanning of a target with known geometric features mimicking fingerprint features can be examined as images or surface plots and analyzed for fidelity against the known target feature specifications to evaluate or validate device capture performance as well as interoperability. The target can be used by scanner vendors and designers to validate their devices, as well as to perform type certification.

Abstract: Systems and methods for controlling the temperature of small volumes such as yoctoliter volumes, are described. The systems include one or more plasmonic nanostructures attached at or near a nanopore. Upon excitation of the plasmonic nanostructures, such as for example by exposure to laser light, the nanoparticles are rapidly heated thereby causing a change in the ionic conductance along the nanopore. The temperature change is determined from the ionic conductance. These temperature changes can be used to control rapid thermodynamic changes in molecular analytes as they interact with the nanopore.

Abstract: A multilayered optical tissue phantom fabrication approach and inherently produced test target structure which address the issues of of optical conformity known in the art by controlling the formation of micrometer scale monolayers embedded with light-scattering microspheres.

Abstract: A nanostructure sensing device comprises a semiconductor nanostructure having an outer surface, and at least one of metal or metal-oxide nanoparticle clusters functionalizing the outer surface of the nanostructure and forming a photoconductive nanostructure/nanocluster hybrid sensor enabling light-assisted sensing of a target analyte.

Abstract: A microwave-frequency source at frequency fM comprises: a dual optical-frequency reference source, an electro-optic sideband generator, an optical bandpass filter, an optical detector, a reference oscillator, an electrical circuit, and a voltage-controlled oscillator (VCO). The sideband generator modulates dual optical reference signals at v2 and v1 to generate sideband signals at v1±n1fM and v2±n2fM. The bandpass filter transmits sideband signals at v1+N1fM and v2?N2fM. The optical detector generates a beat note at (v2?N2fM)?(v1+N1fM). The beat note and a reference oscillator signal are processed by the circuit to generate a loop-filtered error signal to input to the VCO. Output of the VCO at fM drives the sideband generator and forms the microwave-frequency output signal. The resultant frequency division results in reduced phase noise on the microwave-frequency signal.

Abstract: A system and method for imaging and aligning antennas that includes an overlay imaging aligner composed of two or more antennas in association with a polarization gate, a polarization beam splitter, a non-polarizing beam splitter, a beam dump, one or more imaging lens and a common detector array. The overlay imaging aligner aligns the antennas by overlaying simultaneous digital images associated with the antennas on the common detector array. The antennas can be, for example, mm Wave antennas, waveguides, etc. The detector array generates real-time digital images the antennas. Such an approach of simultaneous imaging leverages the spatial resolution of digital optical imaging to aligning antenna components.

Abstract: A contactless, three-dimensional fingerprint scanner apparatus, method, and system are described. The contactless fingerprint scanner can provide either, or both, topographical contrast of three-dimensional fingerprint features and optical contrast of a three-dimensional fingerprint surface. Data captured from scanning of a target with known geometric features mimicking fingerprint features can be examined as images or surface plots and analyzed for fidelity against the known target feature specifications to evaluate or validate device capture performance as well as interoperability. The target can be used by scanner vendors and designers to validate their devices, as well as to perform type certification.

Abstract: An apparatus and technique are used to fabricate optical microresonators. A fabrication chamber contains all fabrication materials and devices. The microresonators are fabricated from a glass preform mounted on a motorized spindle. A laser is focused onto the preform to partly or fully impinge on the preform. The laser's focus position is controlled by changing the positioning of a lens mounted on a translation stage. Piezoelectric control elements may be mounted to finished microresonators to control of nonlinear parametric oscillation and four-wave mixing effects of the microresonator, control of nonlinear optical stimulated Brillouin scattering and Raman effects of said microresonator and wideband tuning of the frequency spacing between the output modes of a nonlinear-Kerr-effect optical frequency comb generated with said microresonator.