A variety of nanostructures are provided having a metal nanowire having a plurality of faces extending along a length of the nanowire, and a plurality of semiconductor nanorods forming two or more nanorod arrays, wherein each of the nanorod arrays is attached to a different surface of the nanowire. For example, in some embodiments, the nanostructure is a silver nanowire having a pentagonal cross section and five faces extending along the length of the nanowire, and metal oxide nanorods forming five nanorod arrays extending along each of the five faces of the silver nanowire. The nanostructures can demonstrate high temperature coefficients of resistance, and can be used in a variety of bolometric materials. In some embodiments, bolometric materials are provided including a plurality of the nanostructures deposited onto a surface of a substrate. Methods of making the nanostructures and bolometers are also provided.

An example objective of the present invention is to provide a bolometer capable of reducing its manufacturing cost. A bolometer according to an example aspect of the present invention includes: a substrate; a heat insulating layer formed on the substrate; and a bolometer film formed on the heat insulating layer; wherein the bolometer film is a carbon nanotube film including semiconducting carbon nanotubes in an amount of 67% by mass or more of the total amount of carbon nanotubes, and the thickness of the carbon nanotube film is in the range of 10 nm to 1 μm, and the density of the carbon nanotube film is 0.3 g/cm.sup.3 or more.

The present invention relates to an electromagnetic wave absorbing/radiating material which includes: a conductor; and a plurality of conductor discs disposed in an array above the surface of the conductor or a perforated conductor layer with a plurality of holes defined in an array above the surface of the conductor.

We disclose an array of Infra-Red (IR) detectors comprising at least one dielectric membrane formed on a semiconductor substrate comprising an etched portion; at least two IR detectors, and at least one patterned layer formed within or on one or both sides of the said dielectric membrane for controlling the IR absorption of at least one of the IR detectors. The patterned layer comprises laterally spaced structures.

A photothermal converter using a wavelength selective perfect absorber made of a low-loss metal material or dielectric and a heat detection sensor are combined to develop a sensor that efficiently converts light of a specific wavelength into heat and further electrically detects the heat. Here, since the wavelength selective perfect absorber of the present invention has a periodic structure, it has high directivity, and can also be used as a small motion sensor or a watching sensor using detection of thermal radiation. In addition, it can also be used as a high-precision small position sensor by being combined with a laser light source matching the resonance wavelength of the sensor.

A multi-purpose Micro-Electro-Mechanical Systems (MEMS) thermopile sensor able to use as a thermal conductivity sensor, a Pirani vacuum sensor, a thermal flow sensor and a non-contact infrared temperature sensor, respectively. The sensor comprises a rectangular membrane created in a silicon substrate which has a thin polysilicon layer and a thin residual thermal reorganized porous silicon layer both attached on its back side, and configured to have its three sides clamped to the frame formed in the silicon substrate which surrounds and supports the membrane and the other side free to the frame, a cavity created in the silicon substrate, positioned under the membrane and having its flat bottom opposite to the membrane, its three side walls shaped as curved planes and the other side wall shaped as a vertical plane, a heater or an infrared absorber positioned on the membrane, close to and parallel with the free side of the membrane and a thermopile positioned on the membrane and consists of several thermocouples connected in series and having its hot junctions close to the heater and its cold junctions extended to the frame.

The present application discloses a nonlinear optical crystal material, preparation method and application of the nonlinear optical crystal material. The nonlinear optical crystal material has an excellent infrared nonlinear optical performance, whose frequency-doubling intensity can reach 9.3 times of AgGaS.sub.2 with the same particle size, and it meets type-I phase matching; and its laser damage threshold can reach 7.5 times of AgGaS.sub.2 with the same particle size. The nonlinear optical crystal material has important application value in the frequency-converters which can be used for frequency doubling, sum frequency, difference frequency, optical parametric oscillation of laser in mid and far infrared waveband, and the like.

An infrared (IR) detector comprises a radio frequency (RF) resonator including a bottom electrode to provide acoustic excitation, a piezoelectric layer connected to the bottom electrode and suspended over a cavity defined within a semiconductor substrate, and a top layer comprising a mid-IR metamaterial and which is connected to the piezoelectric layer of the RF resonator. The top layer and the piezoelectric layer are sized to impedance match with a particular IR wavelength, to minimize reflection and maximize absorption of a particular IR wavelength, and thus make the top layer polarization sensitive to the particular IR wavelength.

A method of making a variable emittance window comprising providing a metal foil substrate, applying an antireflection material layer onto the metal foil substrate, applying a protection material layer onto the antireflection material layer, applying a variable emittance material layer onto the protection material layer, annealing to form a two-step variable emittance layer, applying a transparent low emittance material layer to the two-step variable emittance layer, adhering a transparent substrate to the transparent low emittance material layer, and removing the metal foil substrate.

Bi-material terahertz (THz) sensors with metamaterial structures are described. In one embodiment, MEMS fabrication-friendly SiO.sub.x and Al are used to maximize the bi-material effect and metamaterial absorption at 3.8 THz, the frequency of a quantum cascade laser illumination source. Sensors with different configurations were fabricated and the measured absorption is near 100% and responsivity is around 1.2 deg/μW. Fabrication and use of the sensors in focal plane arrays for real time THz imaging is described. In a further embodiment, the metamaterial structure is utilized as a THz emitter when heated by an external source.