摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
Various method and system embodiments of the present invention are directed to implementing serial logic gates using nanowire-crossbar arrays with spintronic devices located at nanowire-crossbar junctions. In one embodiment of the present invention, a nanowire-crossbar array comprises a first nanowire and a number of substantially parallel control nanowires positioned so that each control nanowire overlaps the first nanowire. The nanowire-crossbar array includes a number of spintronic devices. Each spintronic device is configured to connect one of the control nanowires to the first nanowire and operate as a latch for controlling signal transmissions between the control nanowire and the first nanowire.
摘要:
A covert label structure comprising a three dimensional diffracting optical element layer (100) having a depth profile for producing a predetermined pattern, wherein different portions of a top surface of the diffracting optical element layer (100) have at least two different depths relative to a bottom surface of the diffracting optical element layer (100), wherein the depth profile spans across two dimensions of the top surface of the diffracting optical element layer (100), and wherein the top surface reflects light according to the predefined pattern and an overcoat layer (108) over the top surface of the diffracting optical element layer (100) wherein the overcoat layer (108) is opaque to at least one wavelength of light.
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:
A grid heat sink includes primary fins extending from a base and cross fins which intersect the primary fins and form a number of channels. A fan moves cooling air through the channels to remove heat from the primary and cross fins. In one illustrative embodiment, the grid heat sink includes a base, a plurality of intersecting fins, and a plurality of channels formed by the intersecting fins. Each of the channels accept cooling air at an input side of the grid heat sink and direct the cooling air to exit an output side of the grid heat sink.
摘要:
An apparatus for dynamically varying an optical characteristic of a light beam includes an optical element configured to receive a beam of light. The optical element includes at least one sub-wavelength grating formed of a plurality of lines. The apparatus includes at least one actuator connected to at least one component of the optical element and a controller for controlling the at least one actuator to dynamically vary a characteristic of the beam of light that is at least one of emitted through and reflected from the optical element.
摘要:
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.