Abstract: The method of shaping a polycrystalline diamond (PCD) body (exemplarily a wafer of CVD-PCD) utilizes our discovery that the rate and amount of diamond removal from a given region of a PCD body depends, for a given metal "etchant" at a given temperature, on the thickness of the etchant layer overlying the given region, with relatively larger etchant thickness being associated with relatively higher removal rate and amount. Exemplarily, the method can be used to substantially remove thickness variations and/or film curvature from as-produced PCD films. An exemplary metal that can be used in the practice of the invention is mischmetal. The metal etchant can be molten, partially molten or solid.

Abstract: A previously unknown phase of .alpha.-hexathienyl, designated .alpha.-6T/HT, exhibits diffraction peaks at 2.theta.=4.31.degree., 8.64.degree., 12.96.degree., 17.32.degree., 26.15.degree. and 29.08.degree. in a CuK.sub..alpha. powder X-ray diffraction pattern, and is expected to have properties (e.g., high hole mobility) that make the phase desirable for use in, e.g., thin film transistors. Substitution of thin films of .alpha.-6T/HT for prior art organic thin films in thin film transistors and other devices is contemplated.

Abstract: The present invention provides improved methods for making field emission devices by which one can pre-deposit and bond the diamond particles or islands on a flexible metal foil at a desirably high temperature (e.g., near 900.degree. C. or higher), and then subsequently attach the high-quality- emitter-coated conductor foil onto the glass substrate. In addition to maximizing the field emitter properties, these methods provide high-speed, low-cost manufacturing. Since the field emitters can be pre-deposited on the metal foil in the form of long continuous sheet wound as a roll, the cathode assembly can be made by a high-speed, automated bonding process without having to subject each of the emitter-coated glass substrates to plasma heat treatment in a vacuum chamber.

Abstract: The disclosed Mach-Zehnder (MZ)-type devices are planar waveguide devices, with interferometer arms of essentially equal length, with a maximum spacing between the arms (e.g., between the waveguide core centers) selected to make possible simultaneous exposure of both arms to refractive index-altering radiation. Exemplarily the maximum spacing is in the range 20-100 .mu.m. The simultaneous exposure of both waveguides makes it possible to form gratings of essential equal strength, such that typically no individual trimming is required. The resulting devices (typically add-drop filters) are substantially less sensitive to environmental changes (e.g., temperature gradients, mechanical vibrations) than prior art fiber-based devices, and are advantageously used in, for instance, WDM optical communication systems.

Abstract: Heteroepitaxial growth of phosphorus-containing III/V semiconductor material (e.g., InGaAsP) on a non-planar surface of a different phosphorus-containing III/V semiconductor material (e.g., InP) is facilitated by heating the non-planar surface in a substantially evacuated chamber to a mass-transport temperature, and exposing the surface to a flux of at least phosphorus form a solid phosphorus source. This mass-transport step is followed by in situ growth of the desired semiconductor material, with at least an initial portion of the growth being done at a first growth temperature that is not greater than the mass transport temperature. Growth typically is completed at a second growth temperature higher than the first growth temperature. A significant aspect of the method is provision of the required fluxes (e.g., phosphorus, arsenic, indium, gallium) from solid sources, resulting in hydrogen-free mass transport and growth, which can be carried out at lower temperatures than is customary in the prior art.

Abstract: Multistage Er-doped fiber amplifiers (EDFAs) advantageously use high numerical aperture (NA) fiber in the input stage, and low NA fiber in the output stage. The former typically is greater than 0.25, and the latter is less than 0.20. Such amplifiers can have high gain and low noise figure.

Abstract: Electromagnetic resonators according to the invention comprise a first body, exemplarily a split thin ring, that is disposed between two planar field confining plates. The thickness (t) of the first body is less (typically less than 1/2 or 1/10) of the outer radius (R) of the body, and the distance between the first body and the confining plates is less than R. In preferred embodiments the first body comprises superconducting material. Resonators according to the invention can be readily assembled into relatively compact filters that are easily tunable, can have large quality factor, and offer the possibility of single mode operation. Such filters can advantageously be used in, e.g., wireless communications systems.

Abstract: The disclosed novel method of making III/V semiconductor lasers involves cleaving of the wafer along predetermined cleavage planes. A cleavage plane is defined by means of aligned non-continuous depressions. The depressions are spaced from the laser contact regions, and typically are V-grooves produced by photolithography and anisotropic etching. A further surface feature, typically a precisely positioned scribe mark, facilitates cleavage initiation. When carried out in vacuum the novel method can provide high quality, accurately positioned cleavage surfaces, and consequently can facilitate increased yield of high power lasers.

Abstract: Applicant has discovered that aliovalently doped zinc-indium-oxide where In is 40-75% of the metal elements can achieve electrical conductivity comparable to wide band-gap semiconductors presently in use while exhibiting enhanced transparency in both the visible and infrared. The material can be doped to resistivity of less than 1 milliohm-cm by small quantifies of aliovalent dopants, such as tetravalent atoms. It can be deposited on glass substrates in amorphous and polycrystalline films.

Abstract: In accordance with the invention, electronic packages comprising a layer of molded plastic on one side of an insulating substrate are provided with a surrogate layer on the side of the substrate opposite the molded plastic to reduce bending stress. The surrogate layer is preferably thin, has a high coefficient of thermal expansion and is resistant to high tensile stress. Advantageously, the surrogate layer is processed concurrently with the molding of the plastic. Preferred surrogate layers are low temperature thermoplastic sheets, such as acetal plastic sheets, that soften at the molding temperature sufficiently to bond to the substrate. Alternatively, they can be higher temperature rigid materials, such as glass fiber composites, bonded to the substrate with an adhesive layer that cures during molding.

Abstract: A novel non-mechanical optical fiber switch contains a magneto-optic element and a tubular magnet. The magneto-optic element is disposed within the field of the magnet but outside of the magnet bore. The beam of radiation from the switch input to the switch output passes through the axial bore of the magnet. The magnet contains magnetically anisotropic material, preferably a deformation-aged alloy having Fe, Cr and Co as major constituents. The switch is advantageously used in optical fiber communication systems.

Abstract: Near-field optical apparatus according to the invention contains a novel semiconductor laser photon source. The source is capable of providing substantially higher photon flux than prior art near field sources, potentially facilitating read-out rates in the megahertz range in exemplary near-field data storage and retrieval apparatus. The novel source comprises a non-uniform laser emission face, with the emission face configured such that at least 50% of the total radiation emission is from a small (first) region of the emission face, of width less than .lambda..sub.s /2, where .lambda..sub.s is the emission wavelength of the laser. In an exemplary embodiment, a multilayer coating is provided on the emission face, such that radiation emission from the face is relatively low. A recess is formed in the coating such that substantial radiation emission from the recess occurs. The recess constitutes the first region.

Abstract: A device for transmitting radiation is provided. The device includes a glass optical waveguide having a core. A Bragg grating is at least partially formed within the core. Associated with the Bragg grating is a transmission spectrum that includes a band in which incident radiation is attenuated, the peak attenuation being at a wavelength .lambda.. The transmission spectrum of the Bragg grating is such that the full width at half maximum measured in transmission is greater than or equal to (1.5 nm/1558.5 nm) .lambda. and peak attenuation within the band is greater than or equal to 90% of full scale transmission. Attenuation exceeds 50% of the peak attenuation everywhere within the full width at half maximum of the transmission spectrum.

Abstract: Complementary circuits with inorganic n-channel thin film transistors (TFTs) and organic p-channel TFTs can exhibit advantageous properties, without being subject to some of the drawbacks of prior art complimentary inorganic TFTs or complementary organic TFTs. In preferred embodiments of the invention, the n-channel inorganic TFTs have an amorphous Si active layer, and the p-channel organic TFTs have .DELTA.-hexathienylene (.alpha.-6T) active layer. Complementary inverters according to the invention are disclosed, as is an exemplary processing sequence that can be used to manufacture integrated complementary inverters and other complementary circuits according to the invention.

Abstract: A low noise optical fiber Raman amplifier with integral Raman laser (FRA) is disclosed. The FRA typically comprises a fiber ring with at least two amplifier stages, with strictly counter-propagating pump radiation. Relatively short wavelength (e.g., 1060 nm) pump power is provided to the Raman laser portion of the fiber ring. Appropriately selected and placed Bragg gratings provide one or more optical cavities in the fiber ring, such that the input pump radiation is converted to the desired amplifier pump radiation (e.g., 1240 nm, suitable for amplification of 1310 nm signal radiation). The FRA can, for instance, advantageously serve as power amplifier in digital or analog fiber communication systems, or it can serve as pre-amplifier or in-line amplifier.

Abstract: 1.times.2 and more complex switching operations use routing corresponding with guides produced by heating with a laterally-homogeneous layer. Strip heaters, in contact with a silica-based sandwich structure, thermally increase refractive index to define laterally-constrained cores within the center layer.

Abstract: Thermal expansion mismatch between solder and substrate can result in substrate cracking, especially in the case of brittle substrates, e.g., Si or glass. This problem can be substantially eliminated through use of a novel bonding pad structure that comprises a sacrificial layer and a confinement layer disposed on the former, with a window through the latter. The confinement layer (e.g., Ti or Cr) is selected to be substantially inert with respect to the solder (e.g, AuSn) at the soldering temperature, and the sacrificial layer (e.g., Au) is selected to interact with the solder at that temperature, such that the molten solder consumes at least some of the sacrificial material, with the interface between the molten material moving laterally underneath the confinement layer. After re-solidification of the molten material the structure effectively has a distributed interface between the resolidified material and the substrate, with attendant decrease of stress in the substrate.

Abstract: The disclosed method of fusion splicing silica-based optical fiber comprises removing of the polymer coating from the end portions of the respective fibers by contacting the end portions with a chemical polymer remover (e.q., hot sulfuric acid with 5% nitric acid) such that a film of material that comprises the remover remains on the stripped fiber. Typically this is accomplished by refraining from the conventional rinsing of the stripped fiber portions. The film-covered stripped fibers are then fusion spliced in conventional fashion. Splices of strength close to the strength of as-drawn fiber were obtained by this method.

Abstract: The thermal resistivities W.sub.s (=1/.kappa..sub.s) of electrically insulating, crystalline or polycrystalline samples under test (SUTs), all comprising host material such as CVD diamond, can be determined rather quickly once the thermal resistivities W=1/.kappa. of at least two other host crystalline or polycrystalline bodies B.sub.1 and B.sub.2 comprising the same host material as that of the SUTs, and containing the same type of impurity or combination of impurities as the SUTs, are measured by some other technique. These determinations of these thermal resistivities W.sub.s of the SUTs thus require only the measurements of the optical absorptivities .alpha..sub.1 and .alpha..sub.2 and of the thermal resistivities W.sub.1 and W.sub.2, respectively, of at least each of the two other bodies B.sub.1 and B.sub.2 and only of the optical absorptivities .alpha..sub.s of each of the SUTs by such other technique. These determinations of W.sub.

Abstract: In accordance with the invention a planar waveguide device is fabricated by providing a substrate with an undercladding, depositing a particulate layer of core glass on the undercladding, consolidating the particulate layer by low temperature viscous sintering, patterning the consolidated layer to form an optical waveguide and applying an overcladding. The glass layers can be deposited quickly and economically by slurry dipping, centrifuging or electrophoresis. In a preferred embodiment the substrate is silicon, and the core glass is sodium-boro-silicate.