Abstract: Plasmonic activated graphene terahertz (THz) generating devices and generator systems are described based on the excitation of plasma resonances in a graphene element or structure by mixing two signals with a THz difference frequency. The excitation process is the photo-thermo-electric effect which has been demonstrated to be operative at THz frequencies in graphene. An antenna or other electrical component or device, such as an electrical or antenna lead, couples the THz radiation out of the sub-wavelength graphene element.

Abstract: Optical fiber probe tips and methods for fabricating the same are presented. One method entails immersing a distal end of an optical fiber having a cladding and a core into an etching solution and simultaneously etching the cladding and the core using the etching solution for tapering the cladding and the core to form a tapered cladding and a tapered core tip. The optical fiber probe tips are suitable for near-field, scanning, optical microscopy (NSOM).

Abstract: Optical fiber probe tips and methods for fabricating the same are presented. One method entails immersing a distal end of an optical fiber having a cladding and a core into an etching solution and simultaneously etching the cladding and the core using the etching solution for tapering the cladding and the core to form a tapered cladding and a tapered core tip. The optical fiber probe tips are suitable for near-field, scanning, optical microscopy (NSOM).

Abstract: An apparatus and process are described which can measure the strength of an evanescent field at the surface of an optical fiber. Light is injected into an end of the optical fiber while the portion of the fiber to be tested is contacted with a material having a higher index of refraction than the optical fiber. The amount of light lost, i.e., coupled out of the fiber, is a function of the evanescent field strength at the cladding surface of the optical fiber. This loss can be correlated with optical fibers which have thicker and thinner claddings to determine the thickness of the cladding and/or the extent of removal of the cladding by, for example, etching.

Abstract: A frequency shifted cavity apparatus for electromagnetic radiation.

Abstract: A tuned optical fiber grating and a tuning process is disclosed. The gratings on the optical fiber ar tuned so that the reflectance of the grating can occur at a specific wavelength. The process involves encasing that portion of the fiber containing the grating while shining light of the wavelength of desired reflectance through the fiber and stretching the grating until reflectance occurs. Thereafter, the tuned grating is sealed within a tube formed around the tuned grating.

Abstract: A ruggedized grated optical fiber is described. The gratings in the fiber permit its use as a reflector or an interferometer when pairs of gratings having the same reflectance characteristics are spaced along the optical fiber. The ruggedized fiber comprises an optical fiber having the outer cladding removed down to an inner sheathing wherein a portion of the inner sheathing is further removed to expose the core wherein evanescent waves are encountered. The gratings are formed in this core. Surrounding the gratings and connected to the inner sheathing are two semi-tubular sections which are affixed to the inner sheathing and hermetically sealed around the gratings.

Abstract: The invention covers a process of forming gratings in optical fiber. The gratings are formed at depth wherein the evanescent waves of the optical fiber are encountered. The process permits the fabrication of gratings in the optical fiber that reflect light of predetermined wavelengths. The grated optical fibers can be used as reflectors or interferometers when the gratings are used in pairs.