Abstract: The specification describes a Mach-Zehnder electro-optic modulator device in which the ridge containing the waveguides in the interactive electro-optic regions have re-entrant sidewalls. This shifts the peak in the RF field profile to below the surface of the ridge and closer to the peak of the optical field, thereby producing a device with reduced drive voltage.

Abstract: Integrated optical devices which utilize a magnetostrictively, electrostrictively or photostrictively induced stress to alter the optical properties of one or more waveguides in the device are disclosed. The integrated optical devices consist of at least one pair of optical waveguides preferably fabricated in a cladding material formed on a substrate. A stress applying material, which may be a magnetostrictive, electrostrictive or photostrictive material, is affixed to the upper surface of the cladding material near at least one of the optical waveguides. When the appropriate magnetic, electric or photonic field is applied to the stress applying material, a dimensional change tends to be induced in the stress applying material. The constrained state of the stress applying material, however, caused by its adhesion to the cladding material, causes regions of tensile and compressive stress, as well as any associated strains, to be created in the integrated optical device.

Abstract: A technique that involves selective removal of material from a surface of a polycrystalline diamond (polyD) film such that a non-planar surface results. Exemplarily the technique is used to form polyD optical elements, e.g., convex or concave lenses, or Fresnel lenses, including arrays of such lenses. The technique involves maintaining on appropriately shaped hot template body in intimate contact with a polyD surface for a time (e.g., in the range 1-1000 hours) sufficient to result in formation of the desired feature in the polyD surface. The template body involves a rare earth metal (La and Ce are preferred), Mn and/or Fe, and the temperature is below the melting temperature of the template body. Removal of "spent" template material by, e.g., chemical etching and finishing of the polyD feature, e.g., by laser ablation and/or polishing, are contemplated.

Abstract: In accordance with the invention, an optical fiber phase shifter comprises a length of asymmetrical optical fiber disposed perpendicular to a magnetic field for providing a non-reciprocal phase shift. Preferably the fiber is wound in a circular coil and exposed to an axial field as from a pancake magnet. In an isolator, the fiber length and magnet strength are chosen to provide non-reciprocal phase shifts of .+-.45.degree. or .+-.90.degree.. The isolator including the phase shifter can be any of several configurations.

Abstract: An optical system useful, e.g., for near-field scanning optical microscopy is provided. The system incorporates a probe having improved properties. In one embodiment, the probe comprises a tapered and partially metallized portion of a single-mode optical fiber.

Abstract: An optical system useful, e.g., for near-field scanning optical microscopy is provided. The system incorporates a probe having improved properties. In one embodiment, the probe comprises a tapered and partially metallized portion of a single-mode optical fiber.

Abstract: An optical system useful, e.g., for near-field scanning optical microscopy is provided. The system incorporates a probe having improved properties. In one embodiment, the probe comprises a tapered and partially metallized portion of a single-mode optical fiber.

Abstract: An optical system useful, e.g., for near-field scanning optical microscopy is provided. The system incorporates a probe having improved properties. In one embodiment, the probe comprises a tapered and partially metallized portion of a single-mode optical fiber.

Abstract: An optical system useful, e.g., for near-field scanning optical microscopy is provided. The system incorporates a probe having improved properties. In one embodiment, the probe comprises a tapered and partially metallized portion of a single-mode optical fiber.

Abstract: An optical system useful, e.g., for near-field scanning optical microscopy is provided. The system incorporates a probe having improved properties. In one embodiment, the probe comprises a tapered and partially metallized portion of a single-mode optical fiber.

Abstract: The invention relates to optical systems comprising thin film optical waveguide isolators that are characterized by linear birefringence at least some wavelengths and temperatures. Disclosed is a method for using such a system at more than one wavelength and temperature.

Abstract: An optical circulator/isolator is implemented in a semiconductor package formed by a semiconductor substrate, which supports integral thin film waveguide polarization splitters and combiners, and a semiconductor lid, which supports four spherical lenses and a polarization rotator. The latter is a composite of at least two adjacent slabs of optically active material, one slab serving as a nonreciprocal 45.degree. rotator (e.g., a Faraday rotator) and the other as a reciprocal 45.degree. rotator (e.g., half-wave device). The lenses, serving both as beam expanders/condensers and as collimators, are positioned between the waveguide ends and major surfaces of the composite slab. When used with means for reversing the direction of the magnetic field in the nonreciprocal rotator, the device functions also as a switch. Also described are system architectures made possible by these devices; e.g.

Abstract: An optical system, useful as a magnetometer and as a polarization contoller, is disclosed. The system includes a source of electromagnetic radiation, a detector of electromagnetic radiation, and a magnetizable medium via which the source and detector communicate with one another. The system further includes apparatus for forming at least two adjacent magnetic domains separated by at least one domain wall.

Abstract: A method for fabricating a polarization rotator which includes a thin film waveguide exhibiting essentially zero linear birefringence in the absence of an externally applied stress, as well as an optical system incorporating said rotator, is disclosed.

Abstract: An optical system, e.g., an optical fiber communication system or an optical mass storage device, which includes a linearly birefringent polarization rotator useful in an optical isolator or optical circulator, is disclosed. The rotator, which compensates for the effects of linear birefringence and is substantially antireciprocal, includes two or more material regions which are capable of subjecting incident light to elliptic birefringences. However, the sign and/or magnitude of the linear, or the sign and/or magnitude of the circular, components of the elliptic birefringences differ from region to region. Moreover, the length of each region, except the first or last region, is substantially equal to one-half the birefringent period of the region. The length of the first or last region, by contrast, is substantially equal to one-quarter the birefringent period of the region.

Abstract: Crystals of neodymium and praseodymium iron garnet materials have Faraday rotation which render such materials suitable for use, e.g., as antireciprocal components in optical devices and communications systems. These materials can be made by liquid-phase epitaxy on a substrate having suitable lattice parameters, deposition being carried out at relatively low melt temperatures.

Abstract: An optical system, e.g., an optical fiber communication system or an optical mass storage device, which includes a linearly birefringent polarization rotator useful in an optical isolator or optical circulator, is disclosed. The rotator, which compensates for the effects of linear birefringence and is substantially antireciprocal, includes two or more material regions which are capable of subjecting incident light to elliptic birefringences. However, the sign and/or magnitude of the linear, or the sign and/or magnitude of the circular, components of the elliptic birefringences differ from region to region. Moreover, the length of each region, except the first or last region, is substantially equal to one-half the birefringent period of the region. The length of the first or last region, by contrast, is substantially equal to one-quarter the birefringent period of the region.

Abstract: Transfer between paths in ion-implanted magnetic bubble memories has been achieved without the use of transfer conductors. The transfer mechanism takes advantage of the three-fold anisotropy of the implanted drive layer which makes it possible for bubbles to pass freely through gaps in one direction while being obstructed from passing through in the other direction. Transfer is controlled by a brief reversal of the direction of rotation of the in-plane field. In one embodiment, a bidirectional transfer gate is employed. Configurations using unidirectional gates and hybrid gates using conductor and reverse-rotation controlled transfer are also shown.

Abstract: The coercivity of materials that are capable of supporting single wall magnetic domains are measured by an expedient and accurate technique. This technique requires that the material be placed in a static magnetic field having a gradual spatial gradient. Finger shaped domains produced in the material are then modulated by introduction of an AC magnetic field. Coercivity is obtained by measuring the distance the finger domains move due to the AC field.