Abstract: The present invention provides a method for making a high strength, small grain size ceramic having a transgranular fracture mode by rapid densification of a green body and subsequent cooling of the densified ceramic. The ceramic may include dislocations, defects, dopants, and/or secondary phases that are formed as a result of the process and resulting in stress fields capable of redirecting or arresting cracks within the material. This ceramic can maintain transparency from ultraviolet to mid-wave infrared.

Abstract: The present invention provides a method for making a high strength, small grain size ceramic having a transgranular fracture mode by rapid densification of a green body and subsequent cooling of the densified ceramic. The ceramic may include dislocations, defects, dopants, and/or secondary phases that are formed as a result of the process and resulting in stress fields capable of redirecting or arresting cracks within the material. This ceramic can maintain transparency from ultraviolet to mid-wave infrared.

Abstract: Fiber optic amplification includes a photonic crystal fiber coupled to a pump laser through a first coupler. The pump laser emits a first electromagnetic radiation wave into the photonic crystal fiber at a first oscillation frequency and a second electromagnetic radiation wave into the photonic crystal fiber at a second oscillation frequency equaling the first oscillation frequency. The first and second electromagnetic radiation waves interact to generate a signal comprising an electromagnetic radiation wave at a third oscillation frequency and an idler comprising a fourth electromagnetic radiation wave at a fourth oscillation frequency to be generated and amplified through parametric amplification. Parametric amplification is achieved by four wave mixing. The photonic crystal fiber emits a parametric output signal based on the four wave mixing. A nonlinear crystal frequency doubles the parametric output signal through second-harmonic generation.

Abstract: The present invention provides a method for making a high strength, small grain size ceramic having a transgranular fracture mode by rapid densification of a green body and subsequent cooling of the densified ceramic. The ceramic may include dislocations, defects, dopants, and/or secondary phases that are formed as a result of the process and resulting in stress fields capable of redirecting or arresting cracks within the material. This ceramic can maintain transparency from ultraviolet to mid-wave infrared.

Abstract: The present invention provides a method for making a high strength, small grain size ceramic having a trans-granular fracture mode by rapid densification of a green body and subsequent cooling of the densified ceramic. The ceramic may include dislocations, defects, dopants, and/or secondary phases that are formed as a result of the process and resulting in stress fields capable of redirecting or arresting cracks within the material. This ceramic can maintain transparency from ultraviolet to mid-wave infrared.

Abstract: The invention relates to methods for fabricating antireflective surface structures (ARSS) on an optical element using a seed layer of material deposited on the surface of the optical element. The seed layer is removed during or after the etching, and serves to control etching time as well as the transmission region of the optical element having ARSS. Optical elements having ARSS on at least one surface are also provided.

Abstract: A nanoparticle containing monoclinic lutetium oxide. A method of: dispersing a lutetium salt solution in a stream of oxygen gas to form droplets, and combusting the droplets to form nanoparticles containing lutetium oxide. The combustion occurs at a temperature sufficient to form monoclinic lutetium oxide in the nanoparticles. An article containing lutetium oxide and having an average grain size of at most 10 microns.

Abstract: The invention relates to methods for fabricating antireflective surface structures (ARSS) on an optical element using a three-dimensional film layer applied to the surface of the optical element. The methods beneficially permit materials that do not exhibit local variation in physical and chemical properties to be provided with ARSS. Optical elements having ARSS on at least one surface are also provided.

Abstract: A method for producing nanostructured, hydrophilic, transmissive, anti-reflective surfaces is described. The method for providing a hydrophilic surface includes steps of providing a substrate that is transmissive in at least one wavelength in the infrared to ultraviolet range of the electromagnetic spectrum and comprises at least one surface including nanostructures of a size smaller than the at least one wavelength; and functionalizing the at least one surface with hydroxyl groups thereon. This method provides devices having excellent transmittance and anti-reflectance properties and which are resistant to seawater.

Abstract: The present invention is generally directed to a device comprising multiple specialty glass optical fibers that combines several different mid-infrared optical signals from multiple optical fibers into one signal in a single optical fiber. In addition, the present invention provides for a method of making the device.

Abstract: A ?-SiC coating made by the method of mixing SiO2 with carbon and heating the mixture in vacuum wherein the carbon is oxidized to CO gas and reduces the SiO2 to SiO gas and reacting a carbon material, comprising stainless steel with a carbon coating, with the SiO gas at a temperature in the range of 1300 to 1600° C. resulting in a SiC coating on the stainless steel.

Abstract: An antireflection optical element formed from an optical material. The optical material includes a first plurality of antireflective surface structures in the form of first protuberances from the optical material. The first plurality of antireflective surface structures are constructed to aid in transmission of a first wavelength range through the optical material. Also included are a second plurality of antireflective surface structures in the form second protuberances from the first plurality of antireflective surface structures. The second plurality of antireflective surface structures are constructed to aid in transmission a second wavelength range through the optical material. The first wavelength range comprises longer wavelengths than the second wavelength range.

Abstract: A method for creating a random anti-reflective surface structure on an optical fiber including a holder configured to hold the optical fiber comprising a groove and a fiber connector, an adhesive material to hold the optical fiber in the holder and fill any gap between the optical fiber and the holder, a glass to cover the adhesive material and the optical fiber, and a reactive ion etch device. The reactive ion etch device comprises a plasma and is configured to expose an end face of the optical fiber to the plasma. The plasma is configured to etch a random anti-reflective surface structure on the end face of the optical fiber.

Abstract: A method for creating a random anti-reflective surface structure on an optical fiber including a holder configured to hold the optical fiber comprising a groove and a fiber connector, an adhesive material to hold the optical fiber in the holder and fill any gap between the optical fiber and the holder, a glass to cover the adhesive material and the optical fiber, and a reactive ion etch device. The reactive ion etch device comprises a plasma and is configured to expose an end face of the optical fiber to the plasma. The plasma is configured to etch a random anti-reflective surface structure on the end face of the optical fiber.

Abstract: The present invention is directed to a method for making infrared transmitting graded index optical elements by selecting at least two different infrared-transmitting materials, each with a different refractive index, having similar thermo-viscous behavior; assembling the infrared-transmitting materials into a stack comprising one or more layers of each infrared-transmitting material resulting in the stack having a graded index profile; and forming the stack into a desired shape. Also disclosed is the related optical element made by this method.

Abstract: A system and method for creating a random anti-reflective surface structure on an optical fiber including a holder configured to hold the optical fiber comprising a groove and a fiber connector, an adhesive material to hold the optical fiber in the holder and fill any gap between the optical fiber and the holder, a glass to cover the adhesive material and the optical fiber, and a reactive ion etch device. The reactive ion etch device comprises a plasma and is configured to expose an end face of the optical fiber to the plasma. The plasma is configured to etch a random anti-reflective surface structure on the end face of the optical fiber.

Abstract: Fiber optic amplification includes a photonic crystal fiber coupled to a pump laser through a first coupler. The pump laser emits a first electromagnetic radiation wave into the photonic crystal fiber at a first oscillation frequency and a second electromagnetic radiation wave into the photonic crystal fiber at a second oscillation frequency equaling the first oscillation frequency. The first and second electromagnetic radiation waves interact to generate a signal comprising an electromagnetic radiation wave at a third oscillation frequency and an idler comprising a fourth electromagnetic radiation wave at a fourth oscillation frequency to be generated and amplified through parametric amplification. Parametric amplification is achieved by four wave mixing. The photonic crystal fiber emits a parametric output signal based on the four wave mixing. A nonlinear crystal frequency doubles the parametric output signal through second-harmonic generation.

Abstract: A method of purifying a spinel powder includes contacting a spinel powder with an acid solution to form an acid-washed spinel composition and contacting the acid-washed spinel composition with a basic solution to form a purified composition. The purified powder is suited to formation of low-absorption shaped bodies, such as windows for high intensity laser devices.

Abstract: A method for forming a high purity, copper indium gallium selenide (CIGS) sputtering target is disclosed. The method includes sealing precursor materials for forming the bulk material in a reaction vessel. The precursor materials include copper, at least one chalcogen selected from selenium, sulfur, and tellurium, and at least one element from group IIIA of the periodic table, which may be selected from gallium, indium, and aluminum. The sealed reaction vessel is heated to a temperature at which the precursor materials react to form the bulk material. The bulk material is cooled in the vessel to a temperature below the solidification temperature of the bulk material and opened to release the formed bulk material. A sputtering target formed by the method can have an oxygen content of 10 ppm by weight, or less.

Abstract: A method for forming a high purity, copper indium gallium selenide (CIGS) bulk material is disclosed. The method includes sealing precursor materials for forming the bulk material in a reaction vessel. The precursor materials include copper, at least one chalcogen selected from selenium, sulfur, and tellurium, and at least one element from group IIIA of the periodic table, which may be selected from gallium, indium, and aluminum. The sealed reaction vessel is heated to a temperature at which the precursor materials react to form the bulk material. The bulk material is cooled in the vessel to a temperature below the solidification temperature of the bulk material and opened to release the formed bulk material. A sputtering target formed by the method can have an oxygen content of 10 ppm by weight, or less.