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:
Embodiments of the present invention are directed to nanowire-based systems for performing surface-enhanced Raman spectroscopy. In one embodiment, a system comprises a substrate having a surface and a plurality of tapered nanowires disposed on the surface. Each nanowire has a tapered end directed away from the surface. The system also includes a plurality of nanoparticles disposed near the tapered end of each nanowire. When each nanowire is illuminated with light of a pump wavelength, Raman excitation light is emitted from the tapered end of the nanowire to interact with the nanoparticles and produce enhanced Raman scattered light from molecules located in close proximity to the nanoparticles.
摘要:
A waveguide intersection includes an input waveguide and an output waveguide; a crossing waveguide intersecting the input waveguide and the output waveguide to form an intersection; and a block that is optically joined to the intersection such that a guided mode is produced within the intersection. A method of reducing optical losses within a waveguide intersection includes increasing a cross-sectional height of an intersection such that optical energy passing through the intersection is laterally confined.
摘要:
A small-mode-volume, vertical-cavity, surface-emitting laser (VCSEL). The VCSEL includes an active structure to emit light upon injection of carriers, and two reflecting structures at least one of which is a grating reflector structure. The active structure is disposed within at least one of the reflecting structures. The reflecting structures are configured as a vertical-cavity resonator of small mode-volume. An optical-bus transmitter including a plurality of small-mode-volume VCSELs, and a system including at least one optical bus and at least one optical-bus transmitter in a digital-information processor, or a data-processing center, are also provided.
摘要:
Various embodiments of the present invention are directed to compact, sub-wavelength optical resonators. In one aspect, an optical resonator comprises two approximately parallel reflective structures positioned and configured to form a resonant cavity. The resonator also includes a fishnet structure disposed within the cavity and oriented approximately parallel to the reflective structures. The resonant cavity is configured with a cavity length that can support resonance with electromagnetic radiation having a fundamental wavelength that is more than twice the cavity length.
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:
A system for performing Raman spectroscopy comprises a waveguide layer configured with at least one array of features, the at least one array of features being configured to provide guided-mode resonance for at least one wavelength of electromagnetic radiation; and at least one fluid channel disposed in the waveguide layer. An analyte sensor comprises an electromagnetic radiation source configured to emit a range of wavelengths of electromagnetic radiation, the system for performing Raman spectroscopy, and at least one photodetector configured to detect Raman scattered light.
摘要:
Various embodiments of the present invention relate to dynamically reconfigurable hologram comprising a phase-modulation layer and an intensity-control layer. The phase modulation layer comprises an electronically programmable erasable negative index material crossbar. The crossbar includes a first layer of approximately parallel nanowires (502) and a second layer of approximately parallel nanowires (504) that overlay the nanowires in the first layer. The nanowires in the first and second layers have substantially regularly spaced fingers. The crossbar also includes resonant elements (812) comprising two fingers of a nanowire in the first layer, two fingers of a nanowire in the second layer, and an intermediate layer (1006,1302) sandwiched between the nanowire in the first layer and the nanowire in the second layer. The refractive index of each resonant element is controlled by changing the charge density within the intermediate layer.
摘要:
An analyzer is disclosed herein. The analyzer encompasses a substrate having a surface with a plurality of distinct V-grooves formed therein. An input flow channel is configured to intersect and fluidly communicate with each of the plurality of distinct V-grooves at respective input points, and an output flow channel is configured to intersect and fluidly communicate with each of the plurality of distinct V-grooves at respective output points.