Abstract: A tunable waveguide laser includes a laser cavity with a length of polymer waveguide doped with rare-earth elements and having reflectors at either end. The output wavelength of the waveguide laser depends on the configuration of the reflectors, which are generally optical gratings. Temperature control elements, such as resistive heaters, are used to adjust the temperature of the reflectors. The change in temperature causes a change in the configuration of the reflectors resulting in a shift in output wavelength. The temperature of the reflectors are controlled to achieve a desired output wavelength.

Abstract: An object of the present invention is obtaining a semiconductor film with uniform characteristics by improving irradiation variations of the semiconductor film. The irradiation variations are generated due to scanning while irradiating with a linear laser beam of the pulse emission. At a laser crystallization step of irradiating a semiconductor film with a laser light, a continuous light emission excimer laser emission device is used as a laser light source. For example, in a method of fabricating an active matrix type liquid crystal display device, a continuous light emission excimer laser beam is irradiated to a semiconductor film, which is processed to be a linear shape, while scanning in a vertical direction to the linear direction. Therefore, more uniform crystallization can be performed because irradiation marks can be avoided by a conventional pulse laser.

Abstract: A unit has an array of lasers having an emission surface through which beams can be emitted in a substantially vertical direction so as to define an emission side, drive electronics connected to a side opposite to the emission side of the array of lasers, and an array of modulators, located on the emission side of the array of lasers and connected to the drive electronics.

Abstract: One-dimensional nanostructures having uniform diameters of less than approximately 200 nm. These inventive nanostructures, which we refer to as “nanowires”, include single-crystalline homostructures as well as heterostructures of at least two single-crystalline materials having different chemical compositions. Because single-crystalline materials are used to form the heterostructure, the resultant heterostructure will be single-crystalline as well. The nanowire heterostructures are generally based on a semiconducting wire wherein the doping and composition are controlled in either the longitudinal or radial directions, or in both directions, to yield a wire that comprises different materials. Examples of resulting nanowire heterostructures include a longitudinal heterostructure nanowire (LOHN) and a coaxial heterostructure nanowire (COHN).

Abstract: Lasing at the edge of the reflection band or at a defect state within the reflection band of a thin one-dimensional periodic structure is used to create a large-area, thin-film laser source with transverse dimensions that can be much greater than the film thickness. Angular confinement of radiation propagating perpendicular to the layers leads to a spreading of the beam inside the medium which is much greater than the diffraction divergence. This enhances the spatial extent of correlation at the output surface of the thin film. When a pump source induces gain at the lasing threshold in a wide region, a spatially coherent monochromatic light beam is emitted perpendicular to the film surface from the entire gain region. Alternate embodiments of the present invention include a passive spatial filter and an active amplifier.

Abstract: A semiconductor device comprises a substrate having a first thermal expansion coefficient T1, a strain reducing layer formed on the substrate and having a second thermal expansion coefficient T2, and a semiconductor layer formed on the strain reducing layer, having a third thermal expansion coefficient T3, and made of a nitride compound represented by AlyGa1−y−zInzN (0≦y≦1, 0≦z ≦1). The second thermal expansion coefficient T2 is lower than the first thermal expansion coefficient T1. The third thermal expansion coefficient T3 is lower than the first thermal expansion coefficient T1 and higher than the second thermal expansion coefficient T2.

Abstract: A monolithically integrated VCSEL and photodetector, and a method of manufacturing the same, are disclosed for applications where the VCSEL and photodetector require separate operation such as duplex serial data communications applications. A first embodiment integrates a VCSEL with an MSM photodetector on a semi-insulating substrate. A second embodiment builds layers of a p-i-n photodiode on top of layers forming a VCSEL using a standard VCSEL process. The p-i-n layers are etched away in areas where VCSELs are to be formed and left where photodetectors are to be formed. The VCSELs underlying the photodetectors are inoperable, and serve to recirculate photons which are not initially absorbed back into the photodetector. The transmit and receive pairs are packaged into a single package for interface to multifiber ferrules. The distance between the devices is precisely defined photolithographically, thereby making alignment easier.

Abstract: A laser and optical amplifier waveguide device with a plurality of layers that supports a single lowest-order optical mode with gain while higher order modes radiate and have a net loss. The supported lowest-order mode which has gain, has a mode cross section which is large compared to the operating optical wavelength in both the transverse and lateral directions. The contours of constant optical intensity of such lowest-order can be nearly circular, having an approximately elliptical shape with a small aspect ratio.

Abstract: A diamond coating formed on a WC—Co substrate prepared through a process including employing a plasma and a variety of interactions from a multiple laser system demonstrates exceptional adhesion and indicates a durable cubic diamond structure. The coating on the WC—Co substrate is typically between 25 and 40 &mgr;m thick and has an average crystal size of between 10 and 20 &mgr;m. Various methods of confirming the cubic diamond structure of the coatings have been employed. The adhesion of the diamond coating to the substrate is very strong. An electron microprobe analysis shows tungsten and cobalt atoms incorporated into the film and a layer depleted in cobalt exists at the diamond-WC—Co interface. Particulates of WC—Co—C alloy are spread over the top surface, apparently formed by condensation from the vapor phase of metal-containing molecules. Carbon is confirmed as being the main component of the surface layer.

Abstract: The present invention provides an epitaxial wafer comprising, on a p-type GaAs single-crystal substrate, a first p-type layer; a p-type cladding layer; a p-type active layer; and an n-type cladding layer, wherein the n-type cladding layer has a carrier concentration of 1×1017 to 1×1018 cm−3; a sulfur concentration of 3×1016 atoms/cm3 or less; and a thickness of 20-50 &mgr;m. The maximum silicon concentration in the portion of the p-type cladding layer within 2 &mgr;m of the interface between the p-type cladding layer and the first p-type layer is less than 1×1018 atoms/cm3; the concentration of carbon, sulfur, or oxygen in the first p-type layer is less than 1×1017 atoms/cm3; the p-type cladding layer has a thickness of 50-80 &mgr;m; the first p-type layer has a carrier concentration of 3×1017 to 1×1018 cm−3; and the n-type cladding layer contains germanium at a concentration of 3×1018 cm−3 or less.

Abstract: Method and apparatus for processing a workpiece having a thin film layer using laser pulses generated by a plurality of lasers. The lasers are equipped with Q-switches and triggered by a Q-switch trigger device at controlled pulse frequencies and delays with respect to one another. The laser pulses from the plurality of lasers are directed to the same processing spot on the workpiece to generate a combined laser beam, and the workpiece is moved relative to the laser beam to process the thin film with the laser pulses. The method and apparatus increase the processing speed and accomplish multiple-step processing in a single pass. Application of the invention in the fabrication of thin film solar cells is described.

Abstract: In a guiding structure having a corrugation, depth of the corrugation is changed in the axial direction to change the effective refractive index by a considerable amount. The use of a 2nd-order or higher-order corrugation is desirable to ensure precise processing. It is also desirable that changes in depth is continuous. In a DFB laser using this structure, effective phase shifting and optical confinement factor can be controlled by changing the depth of the corrugation. In a DFB laser/modulator integrating device commonly using an active layer and an absorption layer, changes of the corrugation in the axial direction, including the presence or absence thereof, can considerably change optical confinement factor to the absorption layer and the active layer.

Abstract: A thin film laser emitting device includes a Bragg reflector including a recess and one or more diffraction gratings provided around the recess, a thin film laser layer formed in the recess, for generating lights, the lights being reflected by the diffraction gratings, a pair of electrodes, provided in the recess to have the thin film laser layer therebetween, and a laser emitting means, provided at a portion of the gratings, for emanating the reflected lights.

Abstract: A compound planar waveguide comprising multiple confinement structures that provides independent containment of pump and laser radiation. The waveguide may be formed of multiple layers of laser-active and laser-inactive materials to provide step changes in refractive index. The planar waveguide may include a central laserable core layer substantially sandwiched by at least two non-laserable cladding layers to provide an interface between the inner surfaces of the cladding layers and the gain medium core to define a first waveguide by virtue of an index of refraction discontinuity for containing developed laser radiation, and wherein the outer surfaces of the cladding layers define a second waveguide by virtue of an index of refraction discontinuity for containing pump radiation within the waveguide. The second waveguide may be also defined by an interface formed between the cladding layers and additional non-laserable external layers which sandwich the cladding layers.

Abstract: An organic laser according to the invention comprises an electrically pumped source of incoherent radiation with organic active region, and further comprises a waveguide structure that receives the incoherent radiation. The core of the waveguide comprises organic material that absorbs the incoherent radiation and emits coherent radiation of longer wavelength. The laser forms a unitary structure, with the source of incoherent radiation being close to the waveguide core, exemplarily less than 10.lambda. from the core, where .lambda. is the laser wavelength. Exemplarily the laser is embodied in a planar waveguide laser, in a microdisk laser, or in a laser comprising a photonic bandgap structure.

Abstract: A waveguide optical amplifier include a substrate and a guiding or active layer. The substrate has a substrate surface and a substrate index of refraction. The guiding layer is of Zirconium dioxide (ZrO.sub.2) and/or Alumina (Al.sub.2 O.sub.3) and is carried on a cladding layer over the substrate surface. The guiding layer has a guiding layer index of refraction which is higher than the cladding index of refraction. The Zirconium dioxide guiding layer is doped with rare earth materials.

Abstract: In a laser device, notably for optical pumping, the wafer includes an expansion segment adjacent the exit to prevent degradation of the exit facet of the semiconductor wafer that constitutes the amplifying part of the laser. The other facet is reflective and a Bragg grating is formed in a coupling fiber disposed near the exit facet. Applications include optical pumping of erbium-doped fiber amplifiers.

Abstract: A first half-mirror, a buffer layer, a second half-mirror, a transparent electrode, an organic luminescent layer and a metal electrode which also serves as a reflector are formed on a transparent substrate thereby to constitute a first resonator between the second half-mirror and the metal electrode and a second resonator between the first half-mirror and the metal electrode. Light output of a desired wavelength is obtained from the light emitted from the organic luminescent layer utilizing resonance characteristics of the first and second resonators.

Abstract: An integrated-optic sensor includes a waveguide made from a substrate that is doped with rare-earth elements. A beam of light propagating along the waveguide excites these elements, causing them to emit light and thereby increase the total amount of light being propagated in the waveguide. The waveguide itself functions as a laser, so that any change in an optical property of an analyte material which forms a portion of the laser cavity can affect the operation of the laser. Consequently, the wavelength or power of light produced by the laser changes, in direct response to changes in the concentration of a material being sensed, and these changes are enhanced due to the inherent gain characteristics of the laser media.

Abstract: The present invention is directed to methods and apparatus for detecting species in a laser cavity. According to one preferred embodiment, a device according to the invention includes: a source of excitation energy at a first wavelength; a first optic fiber; a resonant cavity; an absorption element; and a detector element. The first optic fiber has at least a first portion which is lasant-doped, and is optically coupled to the excitation source. The doping causes the first optic fiber to amplify light. Thus, in response to light coupled from the excitation source, the first optic fiber is capable of lasing. The resonant cavity surrounds the first portion of the optic fiber and has at least a first wavelength-specific reflector, such that laser light at only a second wavelength is amplified in the cavity. The absorption element can expose a sample to the light contained within the resonant cavity. The detector is optically coupled to the resonant cavity.

Abstract: A heterojunction semiconductor device has a plurality of ordered phase alloy layers. Either the whole or a part of each of the ordered phase alloy layers has a crystal structure (triple-period structure) in which the ordered alloy is of a composition corresponding to the [111]A direction and an anion composition modulation period that is triple that of a disordered structure. The double-period structure may alternatively be used. The triple-period or double-period structure applied to the layer structure of the heterostructure semiconductor device results in a reduction of the bandgap.

Abstract: A resonance type variable wavelength luminescent device which can control a spectrum of emission light of luminescent elements in response to an input signal such as voltage, heat, pressure, sound wave, magnetic field, electric field, gravity, electromagnetic wave or the like. Sequentially formed as laminated on a glass substrate are a semi-transparent reflective film, first electrically conductive transparent electrode films, a variable optical length layer, second electrically conductive transparent electrode films, a hole injection layer, an active layer made of aluminum chelate or the like and metallic electrodes, so that the first and second electrically conductive transparent electrode films are mutually arranged in a matrix form.

Abstract: A laser including a resonant cavity having a solid amplifier medium (1, 7, 8), an inlet mirror (2, 9, 10), an outlet mirror (3, 11, 12, 21), and an optical pumping device (5, 13, 16) to emit at least one pumping beam from the amplifier medium. The laser is operable to vary the direction of the pumping beam in the amplifier medium, and the cavity possesses a geometry enabling a laser beam to be generated, irrespective of the direction of the pumping beam.

Abstract: Method of processing, e.g., laser annealing, objects such as semiconductor devices with pulsed lasers with high production yield and high reproducibility so as to obtain good characteristics stably. The pulse width of the irradiated pulse beam is set to more than 30 nsec to stabilize the processing. To achieve a pulse width exceeding 30 nsec, plural lasers are connected in series or in parallel and excited successively.

Abstract: Optical microcavities are potentially useful as light emitters for, e.g., flat panel displays. Such microcavities comprise a layer structure, including two spaced apart reflectors that define the cavity, with a layer of organic (electroluminescent) material disposed between the reflectors. We have discovered that a microcavity can simultaneously emit radiation of two or more predetermined colors such that the emission has a desired apparent color, exemplarily white. Emission of two or more colors requires that the effective optical length of the cavity is selected such that the cavity is a multimode cavity, with the wavelengths of two or more of the standing wave modes that are supported by the cavity lying within the emission region of the electroluminescence spectrum of the active material.

Abstract: A phase shift device for a laser beam has a circular first area transparent so the laser beam and a second area provided around the first area and transparent to the laser beam. The first and second areas generate a phase difference for example 180.degree. in the passing light beams. The phase shift device is positioned for example at a beam waist of a laser scanning apparatus to form a beam spot of a diameter smaller than that defined by the numerical aperture of the imaging optical system. Structure of a laser apparatus employing such phase shift device is also disclosed.

Abstract: By growing semi-insulating CaF.sub.2 films (296) on a silicon substrate (240), forming superlattice structures (260) made of CaF.sub.2 :Nd and other semiconductor layers (294) and by associating a co-dopant with Nd in the CaF.sub.2 films photoluminescence efficiency of CaF.sub.2 films is increased. This permits using electrons to produce photons and controlling optoelectronic devices using CaF.sub.2 films through voltage variation.

Abstract: A multiwavelength upconversion waveguide laser producing visible or ultraviolet wavelength radiation comprising a semiconductor laser diode producing relatively long wavelength radiation, a channel waveguide having a thin film material which converts the relatively long wavelength radiation into visible or ultraviolet wavelength radiation, and a optical resonator which recirculates the visible or ultraviolet wavelength radiation. The optical resonator may use an output optical coating or one or more Bragg grating reflectors as an output coupler. One or more optical resonators may be used to produce one or more visible or ultraviolet radiation wavelengths. One or more independently controllable lightwave modulators are used to modulate the visible or ultraviolet wavelength radiation.

Abstract: A self-frequency-doubler laser element having a three-dimensional optical waveguide includes a first transparent insulating substrate having both a DFB grating and a grating reflector formed on one side of the DFB grating, a Nd.sup.3+ -ion-doped thin glass film laid over the first transparent insulating substrate, a thin nonlinear optical film laid over the thin glass film, a second transparent insulating substrate laid over the thin nonlinear optical film, and a thin reflecting film laid over the second transparent insulating substrate, wherein the following conditions are satisfied: nf-ng=0.01 to 0.05, and nf and ng are greater than ns and nc, where ns, ng, nf, and nc are the refractive indices of the first transparent insulating substrate, the thin glass film, the thin nonlinear optical film, and the second transparent insulating substrate, respectively.

Abstract: By growing semi-insulating CaF.sub.2 films (272) on a silicon substrate (240), forming superlattice structures (260) made of CaF.sub.2 :Nd and other semiconductor layers (294) and by associating a co-dopant with Nd in the CaF.sub.2 films photoluminescence efficiency of CaF.sub.2 films is increased. This permits using electrons to produce photons and controlling optoelectronic devices using CaF.sub.2 films through voltage variation.

Abstract: A silicon-based microlaser formed of rare-earth-doped CaF.sub.2 thin films has a semiconductor substrate material (240) and a CaF.sub.2 film layers (234) grown on semiconductor substrate material (240), The CaF.sub.2 film layer (234) is doped with a predetermined amount of rare-earth-dopant that is sufficient to cause a spectral emission from the CaF.sub.2 film layer (234) having a narrow linewidth when the CaF.sub.2 film layer (234) is optically or electrically pumped.

Abstract: A semiconductor heterostructure laser cavity is disclosed which has semiconductor layers epitaxied to define four zones on a substrate. The laser cavity includes a first zone with a composition that varies continuously from a first face to a second face with a gap decreasing from the first face to the second face, the first zone ensuring an optical confinement and light guidance. A second zone constitutes an active emission zone in contact with the second face of the first zone and having at least one quantum well with a gap smaller than that of the first zone. A third zone has a gap larger than that of the at least one quantum well. The third zone ensuring an optical confinement and a light guidance, and having a composition which varies continuously from a first face to a second face with a gap which increases from the first face to the second face, the first face of the third zone being in contact with the active emission zone.

Abstract: An improved broad area surface emitting distributed feedback semiconductor laser diode device (10) includes a P-side ohmic contact (28) and an N-side ohmic contact (36). A potential difference is applied across these contacts to create an electric field that induces a stimulated emission of coherent photon radiation. The coherent photon radiation produced by the stimulated emission process is incident upon a second order grating having a curved pattern incorporated therein (29). An output beam, directed normal to a chemically etched output window (38), is produced by a first order diffraction of photon radiation from the surface of the second order curved grating (29). The output beam has a more uniform lateral mode near-field output intensity profile and a more uniform lateral mode near-field phase. The output beam also has a desired single-lobed lateral mode far-field output intensity profile. Moreover, the device (10) concentrates approximately 1 Watt of power into this single lateral mode far-field lobe.

Abstract: This invention covers apparatus for providing a compact, high resolution waveguide optical demultiplexer or spectrometer for application in optical communications. With this invention, incoming light composing many discrete wavelengths or optical channels is spectrally resolved by the waveguide demultiplexer such that the wavelength channels are separated spatially. The two major elements of this invention are a waveguide having a partial mirror along its length to reflect optical frequencies therein, and an optical resonator where one of its resonating mirrors is the partial mirror of the waveguide. Selected frequencies are then extracted from the waveguide and resonated in the resonator.

Abstract: Passive waveguides within a monolithic semiconductor structure are coupled to angled facets to reduce the reflectivity of the angled facets and thereby increase the gain available from for the amplification waveguides coupled to the passive waveguides.

Abstract: An integrated optical component structure designed to operate at a rare earth ion fluorescence wavelength .lambda..sub.1 comprises at least a thin layer of a mixed rare earth fluoride solid solution having the formula (1-x)(M.sub.1-y M'.sub.y F.sub.2)-x TRF.sub.z deposited on a substrate of a monocrystalline semiconductor material where M and M' denote an alkaline earth ion, TRF.sub.z denotes a rare earth fluoride, x is in the range ]0,1[ and y is in the range [0,1]. The component structure finds applications in telecommunications using optical waveguides.

Abstract: An object of this invention is to provide a pulsed laser beam source device which is easy to handle and is operative stably. Pumping light is irradiated to a laser medium from a light source for optical pumping. The stimulated laser medium pumps radiation of a set wavelength. This radiation is stimulated to be amplified while reciprocating between resonator mirrors. A multi layer film is inserted in an optical path of the radiation. Feeble light of the radiation from the laser medium is absorbed by the multi-layer to be weaker, and that part of the radiation having intensities above a set intensity is compressed in terms of time to be emitted outside. The emitted radiation has a very short pulse duration.

Abstract: Optically pumped laser minicavity, its production process and laser using said cavity, wherein the minicavity comprises an electrically insulating, parallelepipedic, solid emitter (1b), having two polished parallel lateral faces (6, 8), a monocrystalline substrate (2) and several monocrystalline layers epitaxied on the substrate and having in directions parallel to said faces a hardness equal to that of the substrate, one of the layers constituting a guide layer (4) able to guide the light emitted by the emitter and the pumping light and another layer (12) constituting a non-guiding protective layer, the protective layer and the substrate constituting two opposite faces of the emitter perpendicular to the lateral faces, laser activating ions being contained within the substrate and/or in one of the layers. In the case of an internal cavity, semi-reflecting mirrors (9, 10) are placed on the lateral faces of the emitter.

Abstract: What is disclosed is a semiconductor ridge waveguide laser structure having mechanical protection of ridge element by means of a thick, multi-layer organic material. The organic material, which may be a polyimide film, is deposited over the ridge element. The present invention also provides a fabrication process for depositing the protective means on the ridge element including deposition and photolithographic steps.

Abstract: An optical harmonic generating device is provided with reverse polarization layers which are made of non-linear optical crystal polarized in a lower direction and are periodically arranged at regular intervals, a non-reverse polarization layer which is made of the non-linear optical crystal polarized in the upper direction and is arrange to surround the reverse polarization layers, a wave guide penetrating through alternate rows of the reverse and non-reverse polarization layers, a first electrode arranged on the wave guide, and second electrodes arranged on both ends of the alternate rows. Electric field is induced between the first and second electrodes through the wave guide to change a refractive index of the reverse and non-reverse polarization layers.

Abstract: A method of selectively tuning the bandedge of a semi-conductor heterostructure includes forming a disordered region which is spatially separated from a quantum well active region, and subsequently annealing the heterostructure so that vacancies/defects in the disordered region diffuse into the quantum well region and enhance interdiffusion at the well-barrier heterojunctions. The tuning is spatially selective when the heterostructure is masked so that exposed portions correspond to regions where bandgap tuning is desirable. The heterostructures of interest are III-V material systems, such as AlGaAs/GaAs, where the active region includes structures such as a single quantum well, a multiple quantum well, or a superlattice.

Abstract: Non-normal plane wave electromagnetic scattering from active guiding structures, such as dielectric films, generates large resonances at discrete plane-wave angles of incidence relative to an interface with the active film. These resonances are generated from a "leaky" wave phase matching condition. Enhancement in the scattered field intensities on the order of 100 is achieved using finite diameter pump and probe laser beams and active films as thin as 6 microns. Solid state and dye lasers with unique characteristics are obtained. Oscillators, amplifiers, gyroscopic and nonlinear laser applications employing the active guiding structure or film provide enhanced performance.

Abstract: A guided-mode resonance filer is provided which can be used as an optical filter with very narrow line width and as an efficient optical switch. Diffraction efficiencies and passband frequencies are calculated based on guided-mode resonance properties of periodic dielectric structures in a waveguide geometry. The guided-mode resonance filter preferably includes means for changing various parameters within the grating so as to change passband frequencies in response thereto. Also, the present invention envisions a narrowband tuneable laser having a diffraction grating of the present invention placed within a laser cavity to provide narrowband optical wave output from the narrowband tuneable laser In another preferred embodiment, the present diffraction grating can be supported by a semiconductor substrate, preferably adjacent to a semiconductor laser for fine-tuning the output of the semiconductor laser.

Abstract: An optical terminal has optical waveguides, 3-dB couplers, laser diodes, laser diodes provided with gratings, and connections on a substrate made of semiconductor material. The grating laser diodes have an external cavity which is formed by the waveguides and delimited by mirrors. Each of the laser diodes has a respective electrical connection through which the diodes can be switched between a light-absorbing mode, a light-amplifying mode, and a light-emitting mode, with the aid of electric current signals, and the diodes are also able to detect a light signal. The terminal can perform a number of functions. A light signal can be received, detected, amplified, and further transmitted. A narrow band light signal of desired wavelength can be generated within a broad wavelength area through the grating diodes in the cavity, and amplified and further transmitted.

Abstract: An optical amplifier in the 1.26 .mu.m to 1.34 .mu.m spectrum range, comprising a solid substrate of fluoride glass doped with praseodymium in which a three-dimensional monomode waveguide is formed having an index difference .DELTA.n relative to the index of the fluoride glass lying in the range 4.times.10.sup.-3 and 8.times.10.sup.-2, said waveguide being associated by coupling means to an optical pump having a wavelength equal to 1.02 .mu.m .+-.0.1 .mu.m.

Abstract: An optical bandpass filter comprises a waveguide region for guiding an optical beam from an input end to an output end, a clad structure provided above and below the waveguide region for confining the optical beam therein, a plurality of quantum well boxes formed in the waveguide region with respectively different quantum levels for selectively absorbing an optical component in the incident optical beam that causes a resonant absorption with the quantum level of the quantum well box, a barrier region provided in the waveguide region for surrounding each of the plurality of quantum well boxes with respect to all of three-dimensional directions and comprising a material having a second band gap that is substantially larger than said first band gap, and window means provided on the clad structure for directing a control optical beam such that the control optical beam irradiates the plurality of quantum well boxes.

Abstract: A semiconductor optical waveguide comprises a substrate of a semiconductor material doped to a first conductivity type, a multiple quantum well layer provided on the substrate for guiding an optical beam, a clad layer doped to a second conductivity type and provided on the multiple quantum well layer for confining the optical beam, a first electrode provided on the upper major surface of the clad layer for injecting carriers of a first type into the quantum well layer, and a second electrode provided on the lower major surface of the substrate for injecting carriers of a second type into the quantum well layer, wherein multiple quantum well layer comprises an alternate stacking of: a quantum well layer having a composition set to provide a smallest band gap that is possible under a constraint that the quantum well layer maintains a lattice constant with the substrate and a thickness set with respect to the optical energy of the optical beam such that a discrete quantum level of carriers is formed in the quant

Abstract: In a thin film micro-optic gyroscope (MOG) (10) a waveguide resonator structure (14) has an optical transmission path formed within a surface of a substrate (12). In one embodiment the path includes a predetermined amount of dopant (12a) for providing regenerative gain to radiation of a predetermined wavelength propagating through the path. The dopant is provided at a predetermined concentration and is substantially uniformly distributed throughout the path. By example, the substrate is comprised of neodymium-doped glass. A pump source is optically coupled to the path for exciting the dopant to emit radiation, the pump source providing radiation at a wavelength of approximately one-half of the predetermined wavelength. For the example of neodymium-doped glass the predetermined wavelength is 1.06 microns.

Abstract: A resonantly photo-pumped x-ray laser (10) is formed of a vanadium (12) and titanium (14) foil combination (16) that is driven by two beams (18, 20) of intense line focused (22, 24) optical laser radiation. Ground state neon-like titanium ions (34) are resonantly photo-pumped by line emission from fluorine-like vanadium ions (32).

Abstract: Method of processing, e.g., laser annealing, objects such as semiconductor devices with pulsed lasers with high production yield and high reproducibility so as to obtain good characteristics stably. The pulse width of the irradiated pulse beam is set to more than 30 nsec to stabilize the processing. To achieve a pulse width exceeding 30 nsec, plural lasers are connected in series or in parallel and excited successively.