Abstract: The present invention introduces a new technique allowing the fabrication of high-aspect ratio nanoscale semiconductor structures and local device modifications using FIB technology. The unwanted semiconductor sputtering in the beam tail region prevented by a thin slow-sputter-rate layer which responds much slower and mostly to the high-intensity ion beam center, thus acting as a saturated absorber funnel-like mask for the semiconductor. The protective layer can be deposited locally using FIB, thus enabling this technique for local device modifications, which is impossible using existing technology. Furthermore, such protective layers allow much higher resolution and nanoscale milling can be achieved with very high aspect ratios, e.g. Ti layer results in aspect ratio higher than 10 versus bare semiconductor milling ratio of about 3.

Abstract: A device for manipulating an object present in a fluid by electrokinetics is disclosed. The device comprises a substrate forming a flow chamber. The device further comprises a plurality of electrically biasable electrode structures and at least one electrically floating electrode structure.

Abstract: A semiconductor device which produces at least 1 W/m2 two photon emission power per area, when operating at one or more temperatures greater than 20 K.

Abstract: A wavelength selective filter device is presented suitable for use as a part of a laser cavity for processing light output of a gain section of the laser cavity. The filter structure comprises a resonator structure including at least one closed-loop resonator; and defines an optical coupler structure for coupling light from an input/output of the gain section to propagate through said resonator structure, and a light reflector structure for reflecting light filtered by said resonator structure to propagate through said resonator structure to said input/output of the gain section. The filter structure is configured so as to define two optical paths of substantially the same lengths for light propagation in the resonator structure from and to the coupler structure.

Abstract: A wavelength selective filter device is presented suitable for use as a part of a laser cavity for processing light output of a gain section of the laser cavity. The filter structure comprises a resonator structure including at least one closed-loop resonator; and defines an optical coupler structure for coupling light from an input/output of the gain section to propagate through said resonator structure, and a light reflector structure for reflecting light filtered by said resonator structure to propagate through said resonator structure to said input/output of the gain section. The filter structure is configured so as to define two optical paths of substantially the same lengths for light propagation in the resonator structure from and to the coupler structure.

Abstract: A tunable semiconductor laser device is presented. The device comprises a laser structure formed by at least two waveguides and an active region located within at least a segment of one of the waveguides; and comprises a tunable spectral filter optically coupled to the laser structure. The tunable spectral filter includes at least two filtering elements, at least one of them being a microring cavity.

Abstract: A multisegment laser diode structure is presented in the form of two spaced-apart linear waveguide segments and two spaced-apart ring-like waveguide segments, arranged such that each of the ring-like segments is optically coupled to each of the linear waveguide segments. At least one of the waveguide segments includes an active lasing material. The waveguide segments are thus arranged such that four separate electrical contacts can be provided to four waveguide segments, respectively, thereby enabling separate driving of each of the waveguide segments.

Abstract: The invention is a waveguide structure (10) that includes two waveguides (90, 94) flanking a coupling region (92) whose effective refractive index is less than those of the waveguides. Outboard of the waveguides are bounding regions (88, 96) whose effective refractive indices decrease inwards adiabatically at the proximal and distal ends of the bounding regions. The waveguides are coupled optically by periodic perturbations of the waveguide geometry, or by reversible uniform or periodic perturbations of the effective refractive indices. In an optical switch matrix based on the waveguide structure, all the waveguides are straight and parallel. A second aspect of the invention is a directional coupler comprising mechanisms for reversibly and quasiperiodically perturbing the effective refractive indices of the waveguides. The respective envelope functions vary monotonically in opposite senses.

Abstract: An optical device for use in data communication technique is presented. The device comprises a combination of two spaced-apart waveguides and at least two spaced-apart resonator-cavity loops. The resonator-cavity loops are accommodated between the two waveguides and connected to each other through sections of the waveguides in such a manner that the resonator-cavity loops and the waveguide sections create a closed loop compound resonator for storing optical energy of a predetermined frequency range. A control means is used for controlling physical characteristics of the compound resonator to adjust its optical storage characteristics.

Abstract: A tunable semiconductor laser device is presented. The device comprises a laser structure formed by at least two waveguides and an active region located within at least a segment of one of the waveguides; and comprises a tunable spectral filter optically coupled to the laser structure. The tunable spectral filter includes at least two filtering elements, at least one of them being a microring cavity.

Abstract: A method of fabricating an integrated optical device and such a device, comprising a structure including at least one waveguiding element are presented. A basic structure is formed containing a substrate material carrying a buffer material layer coated with a core material layer of a higher refraction index as compared to that of the buffer layer. The at least one waveguiding element is defined in a guiding layer on top of the basic structure. The guiding layer is made of a material with a refractive index higher than the refractive index of the buffer layer and the core layer, and is chosen so as to minimize a height of the at least one waveguiding element and to provide effective guiding of light in the core layer.

Abstract: A method of fabricating an integrated optical device and such a device, comprising a structure including at least one waveguiding element are presented. A basic structure is formed containing a substrate material carrying a buffer material layer coated with a core material layer of a higher refraction index as compared to that of the buffer layer. The at least one waveguiding element is defined in a guiding layer on top of the basic structure. The guiding layer is made of a material with a refractive index higher than the refractive index of the buffer layer and the core layer, and is chosen so as to minimize a height of the at least one waveguiding element and to provide effective guiding of light in the core layer.

Abstract: A method of fabricating an integrated optical device and such a device, comprising a structure including at least one waveguiding element are presented. A basic structure is formed containing a substrate material carrying a buffer material layer coated with a core material layer of a higher refraction index as compared to that of the buffer layer. The at least one waveguiding element is defined in a guiding layer on top of the basic structure. The guiding layer is made of a material with a refractive index higher than the refractive index of the buffer layer and the core layer, and is chosen so as to minimize a height of the at least one waveguiding element and to provide effective guiding of light in the core layer.

Abstract: A multisegment laser diode structure is presented in the form of two spaced-apart linear waveguide segments and two spaced-apart ring-like waveguide segments, arranged such that each of the ring-like segments is optically coupled to each of the linear waveguide segments. At least one of the waveguide segments includes an active lasing material. The waveguide segments are thus arranged such that four separate electrical contacts can be provided to four waveguide segments, respectively, thereby enabling separate driving of each of the waveguide segments.

Abstract: An optical coupler, for coupling two waveguides, and an optical switch based on the optical coupler. The indices of refraction of parallel sections of the two waveguides are reversibly perturbed periodically in space to couple low order modes in the two waveguides via a high order mode common to the two waveguides. The waveguides are thus couples with a beat length that may be five or more orders of magnitude shorter than it would be without the periodic perturbations.

Abstract: A method of fabricating an array of vertical-cavity, surface-emitting lasers that allows the lasers to be phase-locked and the resulting device. The growth of the laterally unpatterned epitaxial vertical-cavity structure includes an upper mirror which is only partially reflective. A gold layer supplies the final reflectivity. A grip pattern is then etched in the gold layer, and a lower reflectivity metal layer is deposited over the gold layer and into the grid. The lower reflectivity metal both provides a common contact to the laser elements but also degrades the mirror reflectivity in the grid portion. The lower reflectivity prevents the grid portion from lasing. The areas within the grid pattern are separate lasers, but they are so closely separated that they lase coherently among themselves.

Abstract: A planar array of vertical-cavity, surface-emitting diode lasers, and its method of making. The device comprises an active region having a quantum well region disposed between two Bragg reflector mirrors separated by a wavelength of the emitting laser. A large area of this structure is grown on a substrate and then laterally defined by implanting conductivity-reducing ions into the upper mirror in areas around the lasers. Thereby, the laterally defined laser array remains planar. Such an array can be made matrix-addressable by growing the structure on a conducting layer overlying an insulating substrate. After growth of the vertical structure, an etch or further implantation divides the conducting layer into strips forming bottom column electrodes. Top row electrodes are deposited in the perpendicular direction over the laterally defined top mirrors.