摘要:
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.
摘要:
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.
摘要:
Various embodiments of the present invention are directed to external, electronically controllable, negative index material-based modulators. In one aspect, an external modulator comprises a negative index material in electronic communication with an electronic signal source. The negative index material receives an electronic signal encoding data from the electronic signal source and an unmodulated carrier wave from an electromagnetic radiation source. Magnitude variations in the electronic signal produce corresponding effective refractive index changes in the negative index material encoding the data in the amplitude and/or phase of the carrier wave to produce an electromagnetic signal.
摘要:
Various embodiments of the present invention are directed to nanowire-based photodetectors that can be used to convert information encoded in a channel of electromagnetic radiation into a photocurrent encoding the same information. In one embodiment of the present invention, a photodetector comprises a waveguide configured to transmit one or more channels of electromagnetic radiation. The photodetector includes a first terminal and a second terminal. The first terminal and the second terminal are positioned on opposite sides of the waveguide. The photodetector also includes a number of nanowires. Each nanowire interconnects the first terminal to the second terminal and a portion of each nanowire is embedded in the waveguide.
摘要:
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.
摘要:
Various embodiments of the present invention relate generally to systems for performing Raman spectroscopy. In one embodiment, a system for performing Raman spectroscopy comprises an analyte holder having a surface configured to retain an analyte and a light concentrator configured to receive an incident beam of light, split the incident beam into one or more beams, and direct the one or more beams to substantially intersect at the surface. The system may also include a collector configured to focus each of the one or more beams onto the surface, collect the Raman scattered light emitted from the analyte, and direct the Raman scattered light away from the surface.
摘要:
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.
摘要:
Materials and methods for fabricating and using negative index materials are disclosed. A negative index material comprises a three-dimensional volume including a bulk solution and a plurality of unit cells disposed in the bulk solution in a substantially random pattern. Each unit cell comprises a periodic hole array pattern on a substrate or a resonator formed on a first surface of a substrate, and a thin wire pattern formed on a second surface of the substrate. The combination of the unit cells in the bulk solution produces a negative effective permeability and a negative effective permittivity over a frequency band of interest for the three-dimensional volume. The negative index material may be used to focus radiation by directing an incident radiation at the negative index material and generating a focused radiation by a negative refraction of the incident radiation in the negative index material.
摘要:
Systems and methods employ a layer having a pattern that provides multiple discrete guided mode resonances for respective couplings of separated wavelengths into the layer. Further, a structure including features shaped to enhance Raman scattering to produce light of the resonant wavelengths can be employed with the patterned layer.
摘要:
Systems and methods employ a layer having a pattern that provides multiple discrete guided mode resonances for respective couplings of separated wavelengths into the layer. Further, a structure including features shaped to enhance Raman scattering to produce light of the resonant wavelengths can be employed with the patterned layer.