Abstract: Examples of the present invention include integrated erbium-doped waveguide lasers designed for silicon photonic systems. In some examples, these lasers include laser cavities defined by distributed Bragg reflectors (DBRs) formed in silicon nitride-based waveguides. These DBRs may include grating features defined by wafer-scale immersion lithography, with an upper layer of erbium-doped aluminum oxide deposited as the final step in the fabrication process. The resulting inverted ridge-waveguide yields high optical intensity overlap with the active medium for both the 980 nm pump (89%) and 1.5 ?m laser (87%) wavelengths with a pump-laser intensity overlap of over 93%. The output powers can be 5 mW or higher and show lasing at widely-spaced wavelengths within both the C- and L-bands of the erbium gain spectrum (1536, 1561 and 1596 nm).

Abstract: A hybrid optical source that provides an optical signal having a wavelength is described. This hybrid optical source includes an edge-coupled optical amplifier (such as a III-V semiconductor optical amplifier) aligned to a semiconductor reflector (such as an etched silicon mirror). The semiconductor reflector efficiently couples (i.e., with low optical loss) light out of the optical amplifier in a direction approximately perpendicular to a plane of the optical amplifier. A corresponding optical coupler (such as a diffraction grating or a mirror) fabricated on a silicon-on-insulator chip efficiently couples the light into a sub-micron silicon-on-insulator optical waveguide. The silicon-on-insulator optical waveguide couples the light to additional photonic elements (including a reflector) to complete the hybrid optical source.

Abstract: The invention of the present application provides an SOA-PLC hybrid integrated polarization diversity circuit including a PLC-PBS chip and an SOA-COS whose respective waveguides are coupled to each other. The PLC-PBS chip includes: first and second optical waveguides; a Mach-Zehnder interferometer circuit; and a half-wave plate placed in the first optical waveguide which TM mode light is split into. The SOA-COS includes: a third optical waveguide connected to the first optical waveguide; a fourth optical waveguide connected to the second optical waveguide; and an SOA formed in at least one of the third and fourth optical waveguides. One end of the third optical waveguide and one end of the fourth optical waveguide are connected to a U-turn optical waveguide, the one ends being not connected to the first optical waveguide and the second optical waveguide, respectively.

Abstract: A method, system and article of manufacture for amplification of light for surface enhanced Raman spectroscopy. The method and system include a source of input light, a grating with grooves therein, a nanoparticle array disposed in the grooves with the nanoparticles and grating having a variety of selectable parameters. The combination of the nanoparticles and selected characteristics, including generating hot spots, and the features of the grating enable enhanced amplification of the input light signal to provide an output Raman signal of greatly increased intensity for Raman spectroscopy.

Abstract: A semiconductor optical device includes a first mode converting core, a light amplification core, a second mode converting core, and a light modulation core disposed in a first mode converting region, a light amplification region, a second mode converting region, and a light modulating region of a semiconductor substrate, respectively, and a current blocking section covering at least sidewalls and a top surface of the light amplification core. The first mode converting core, the light amplification core, the second mode converting core, and the light modulation core are arranged along one direction in the order named, and are connected to each other in butt joints. The current blocking section includes first, second, and third cladding patterns sequentially stacked. The second cladding pattern is doped with dopants of a first conductivity type, and the first and third cladding patterns are doped with dopants of a second conductivity type.

Abstract: Provided is a light-emitting device including (a) a layer structure obtained by sequentially growing on a base substrate a first compound semiconductor layer of a first conductivity type, (b) an active layer formed of a compound semiconductor, and (c) a second compound semiconductor layer of a second conductivity type; a second electrode formed on the second compound semiconductor layer; and a first electrode electrically connected to the first compound semiconductor layer. The layer structure formed of at least a part of the second compound semiconductor layer in a thickness direction of the second compound semiconductor layer. The first compound semiconductor layer has a thickness greater than 0.6 ?m. A high-refractive index layer formed of a compound semiconductor material having a refractive index higher than a refractive index of a compound semiconductor material of the first compound semiconductor layer is formed in the first compound semiconductor layer.

Abstract: A device for use in optical signal control is presented. The device comprises an amplification waveguide, including a pumpable medium, and a reference and a control inputs and an output selectively allowing transmission of light respectively into and out of said amplification waveguide. The reference input, the amplification waveguide and the output define together a transmission scheme for reference light through the pumpable medium. The control input and the amplification waveguide define a depletion scheme for the pumpable medium and control light. The device thus allows for controlling an output signal, formed by the transmission of the reference light, by controllable depletion of the pumpable medium.

Abstract: A semiconductor optical amplifier includes: a laminated structure sequentially including a first compound semiconductor layer composed of GaN compound semiconductor and having a first conductivity type, a third compound semiconductor layer having a light amplification region composed of GaN compound semiconductor, and a second compound semiconductor layer composed of GaN compound semiconductor and having a second conductivity type; a second electrode formed on the second compound semiconductor layer; and a first electrode electrically connected to the first compound semiconductor layer. The laminated structure has a ridge stripe structure. When widths of the ridge stripe structure in a light output end face and the ridge stripe structure in a light incident end face are respectively Wout, and Win, Wout>Win is satisfied. A carrier non-injection region is provided in an internal region of the laminated structure from the light output end face along an axis line of the semiconductor optical amplifier.

Abstract: An electrically pumped lateral emission electroluminescent device may include a slotted waveguide including a top silicon layer having a thickness between 150 nm and 300 nm and a refraction index associated therewith, and a bottom silicon layer having a thickness between 150 nm and 300 nm and a refraction index associated therewith. A core layer may include silicon oxide between the top and bottom layers and a thickness less than 70 nm. A core layer refraction index may be greater than each of the top and bottom layer refraction indices. A core layer portion may be in a direction of light propagation and may be doped with erbium, and may include silicon nanocrystals. A portion of each of the top and bottom layers may coincide with the core layer portion and may be doped so that the top and bottom layer portions are electrically conductive to define top and bottom plates.

Abstract: An amplification apparatus includes: a circulator to receive, at a first terminal, first signal light transmitted from OLT to ONU and first light having a predetermined wavelength different from the first signal light and, at a third terminal, second signal light transmitted from ONU to OLT and second light having the predetermined wavelength; a first reflector to output reflected light back to a second terminal; a first optical amplifier to have an amplification band characteristic of amplifying at least the first signal light; a second reflector to output reflected light back to a fourth terminal; a second optical amplifier to have an amplification band characteristic of amplifying the second signal light without amplifying the second light having the predetermined wavelength; and a first partial reflector to have a wavelength transmission characteristic of outputting the light having a wavelength different from the predetermined wavelength to the second optical amplifier.

Abstract: A semiconductor optical amplifier includes a semiconductor substrate, a lower cladding layer formed on the semiconductor substrate, a light absorption layer and an optical amplification layer formed on the lower cladding layer, and an upper cladding layer formed on the light absorption layer and the optical amplification layer. The band gap of a semiconductor material that forms the light absorption layer is wider than the band gap of a semiconductor material that forms the optical amplification layer. The difference between the band gap of the semiconductor material that forms the light absorption layer and the band gap of the semiconductor material that forms the optical amplification layer is 0.12 eV or more.

Abstract: An optical integration circuit includes a semiconductor optical amplifier (SOA), a readout mechanism coupled to the SOA, and an optical filter coupled to an output of the SOA. The SOA has a decaying response function and an input for receiving an optical input signal having a first wavelength. The SOA is configured to output an optical signal representing a temporal integration of the optical input signal. The readout mechanism provides an optical readout signal having a second wavelength to the SOA for measuring a state of the SOA. The optical filter is configured to receive the signal representing the temporal integration of the optical input signal and block optical signals having the first wavelength.

Abstract: An apparatus including a semiconductor optical amplifier configured to amplify an input optical signal, and a controller configured to supply preheat current to the semiconductor optical amplifier when the input optical signal is not input to the semiconductor optical amplifier.

Abstract: It is disclosed a method for driving a laser diode such as to enable mitigation or elimination of so called spiking effects related to the number of injected carriers in the laser overshooting the equilibrium value at the beginning of the lasing process. In this manner, among other things, the efficiency of a master oscillator power amplifier that may be utilized in range finding applications will be improved. It is further disclosed an optical pulse transmitter comprising such a laser diode.

Abstract: An optical amplification control apparatus is formed from a semiconductor optical amplifier, a temperature adjustment unit adjusting the temperature of the semiconductor optical amplifier, and an optical gain control unit adjusting the temperature of the semiconductor optical amplifier by controlling the temperature adjustment unit, and varying an optical gain of the semiconductor optical amplifier. Thus, a pattern effect is suppressed even if the output light intensity (the intensity of amplified light) is increased.

Abstract: An optical amplification device includes: a plurality of semiconductor optical amplifiers to which an optical burst signal is input at a different timing; an optical coupler that combines output signals output from the plurality of semiconductor optical amplifiers; a detection unit that detects an optical inputting to the plurality of semiconductor optical amplifiers; and a control unit that activates one of the semiconductor optical amplifiers where the optical inputting is detected, inactivates the other semiconductor optical amplifier, and remains the activation until another optical inputting is detected in the other semiconductor optical amplifier.

Abstract: An optical sampler includes a first and second 1×n optical beam splitters splitting an input optical sampling signal and an optical analog input signal into n parallel channels, respectively, a plurality of optical delay elements providing n parallel delayed input optical sampling signals, n photodiodes converting the n parallel optical analog input signals into n respective electrical output signals, and n optical modulators modulating the input optical sampling signal or the optical analog input signal by the respective electrical output signals, and providing n successive optical samples of the optical analog input signal. A plurality of output photodiodes and eADCs convert the n successive optical samples to n successive digital samples. The optical modulator may be a photodiode interconnected Mach-Zehnder Modulator. A method of sampling the optical analog input signal is disclosed.

Abstract: The invention relates to optical system including light sources that amplify light using a gain medium. Systems and method of the invention are provided for amplifying light while inhibiting reflections at a peak gain of the gain medium, thereby suppressing parasitic lasing. This allows a system to use a broad range of wavelengths without parasitic lasing, thereby increasing the useable range of a tunable optical filter. In this manner, light at wavelengths not at a peak gain can be used effectively, and the gain medium of an optical amplifier does not limit use of a system to a narrow range of wavelengths associated with a peak gain of the gain medium. A single optical system according to the invention can thus be used for applications that require a broad range of wavelengths.

Abstract: An optical amplifier has a low polarization dependent gain. The amplifier includes a gain medium including a plurality of adjoining semiconductor layers to provide optical gain wherein the adjoining semiconductor layers define one or more quantum wells for electrons and are operative to provide both direct and indirect electron-hole transitions in the gain medium. A first quantized electron energy level in the conduction band and a first quantized hole energy level in the valence band is located in a first layer. A further first quantized hole energy level in the valence band is located in an adjacent second layer.

Abstract: An IR laser source providing light in the IR spectrum, the laser source comprising a pump laser operating at a frequency equivalent to wavelength shorter than 2 ?m and at a predetermined power, and an optic fiber coupled to the pump laser. The optic fiber has at least a section of a hollow core photonic crystal fiber, the at least a section of hollow core photonic crystal fiber being designed to have at least a passband in the IR spectrum and being filled with a molecular gas for triggering at least one Stoke's shift in the light entering the at least a section of hollow core photonic crystal fiber for the particular power of the pump laser, the at least one Stoke's shift be selected to cause the light entering the at least a section of hollow core photonic crystal fiber to shift in frequency into the passband in the IR spectrum of the hollow core photonic crystal fiber.

Abstract: An optical amplifier device comprising an input/output section that inputs incident light and outputs emission light; a polarized light splitting section that causes a polarized light component of the incident light input from the input/output section to branch, and outputs first polarization mode light having a first polarization and second polarization mode light having a second polarization different from the first polarization; a polarization converting section that receives the first polarization mode light, converts the first polarization to the second polarization, and outputs first polarization converted light; and an optical amplifying section that amplifies the first polarization converted light input to one end of a waveguide, outputs the resulting amplified first polarization converted light from another end of the waveguide, amplifies the second polarization mode light input to the other end of the waveguide, and outputs the resulting amplified second polarization mode light from the one end of t

Abstract: An optical-switch driver circuit includes a pulse signal source and a voltage-applying circuit. The pulse signal source generates pulse waves that rise from a first voltage to a second voltage. The voltage-applying circuit, for one of the pulse waves, outputs a voltage higher than the third voltage, then outputs a voltage lower than the third voltage, and further outputs the third voltage.

Abstract: Methods and apparatus are disclosed for wirelessly communicating among integrated circuits and/or functional modules within the integrated circuits. A semiconductor device fabrication operation uses a predetermined sequence of photographic and/or chemical processing steps to form one or more functional modules onto a semiconductor substrate. The functional modules are coupled to an integrated waveguide that is formed onto the semiconductor substrate and/or attached thereto to form an integrated circuit. The functional modules communicate with each other as well as to other integrated circuits using a multiple access transmission scheme via the integrated waveguide. One or more integrated circuits may be coupled to an integrated circuit carrier to form Multichip Module. The Multichip Module may be coupled to a semiconductor package to form a packaged integrated circuit.

Abstract: Optical resonators that are enhanced with photoluminescent phosphors and are designed and configured to output light at one or more wavelengths based on input/pump light, and systems and devices made with such resonators. In some embodiments, the resonators contain multiple optical resonator cavities in combination with one or more photoluminescent phosphor layers or other structures. In other embodiments, the resonators are designed to simultaneously resonate at the input/pump and output wavelengths. The photoluminescent phosphors can be any suitable photoluminescent material, including semiconductor and other materials in quantum-confining structures, such as quantum wells and quantum dots, among others.

Abstract: Embodiments of the present invention provided a method of fabricating a semiconductor light source structure. The method comprises providing a GaAs substrate; forming a lower cladding layer above the substrate, the lower cladding layer comprising an AIxGa1-xAs alloy; forming an active region above the lower cladding layer, the active region comprising a GaAs separate confinement heterostructure; and forming an upper cladding layer comprising an AIxGa1-xAs alloy above the active region in the form of an elongate stripe bounded on either side by an InGaP current-blocking layer, the elongate stripe defining an index-guided optical waveguide.

Abstract: A method and apparatus for implementing a hybrid SOA-Raman amplifier in a central office in order to enable multiple passive optical networks to share one or more enhancement service sources, e.g., to share a source for a broadcast service are disclosed.

Abstract: An optical amplification module has a semiconductor optical amplifier, a package accommodating the semiconductor optical amplifier, and a first connector and a second connector holding respective collimator lenses and arranged in parallel on the package. A sum of bend radii of the first optical fiber and the second optical fiber is greater than a space between the first connector and the second connector.

Abstract: Embodiments generally relate to an optical waveguide component configured for operation with amplitude modulated optical signals at a line rate. The optical waveguide component includes a first optical waveguide segment having a first port and a second port; and a plurality of second optical waveguides each forming a closed loop. Each of the second optical waveguides is electromagnetically coupled to the first optical waveguide exactly once, and each of the closed loops has a round trip time. A product of the line rate and each of the round-trip times is equal to or greater than unity.

Abstract: An optical modulator includes first and second modulation waveguides, a demultiplexer, first and second phase adjustment waveguides that changes phases of a light of the first and second modulation waveguides, a multiplexer that combines light outputs from the first and second phase adjustment waveguides, a gain controller and a modulator bias controller in which voltages of the first and second modulation signals are controlled so that a result of adding light from the first modulation waveguide to light from the second modulation waveguide where light from the first modulation waveguide has a predetermined phase is equal to a result of adding light from the first modulation waveguide to light from the second modulation waveguide where light from the second modulation waveguide has a predetermined phase. A phase-adjustment bias controller that controls phase amounts changed by the first and second phase adjustment waveguides so as to cancel phase errors.

Abstract: The semiconductor optical amplifier device includes a plurality of active units. Each active unit includes an active stripe structure of an optical amplifying medium and a current circuit configured to inject current into the corresponding active stripe structure. Each active stripe structure extends from an input end to an output end. An optical splitter device is configured to split an incoming signal light and for distributing corresponding parts of the incoming signal light into the different input ends of the active stripe structures. The optical splitter device is configured to supply each active stripe structure with the same signals.

Abstract: The present invention is an optical semiconductor device including a lower clad layer 12 having a first conduction type, an active layer 14 that is provided on the lower clad layer 12 and has multiple quantum dot layers 51-55 having multiple quantum dots 41, and an upper clad layer 18 that is provided on the active layer 14 and has a second conduction type opposite to the first conduction type, the multiple quantum dot layers 51-55 having different quantum dot densities.

Abstract: A semiconductor optical amplifier includes an input-side optical amplifier waveguide section that has a first active core layer. An output-side optical amplifier waveguide section connects to the input-side optical amplifier waveguide section and has a second active core layer that is wider than the first active core layer. The width of the first active core layer and relative refractive index difference between the first active core layer and adjacent clad section in the width direction of the first active core layer, and the width of the second active core layer and relative refractive index difference between the second active core layer and adjacent clad section in the width direction of the second active core layer are set such that the carrier density and optical confinement factor in the first active core layer are higher than the carrier density and optical confinement factor in the second active core layer.

Abstract: A wavelength-tunable light source apparatus includes a first light source apparatus and a second light source apparatus. The first light source apparatus is capable of changing an oscillation wavelength and includes a resonator. The resonator includes an optical amplification medium for amplifying light and a waveguide having wavelength distribution. The second light source apparatus is connected to the waveguide and configured to introduce pulsed light as modulation light to the first light source apparatus. The oscillation wavelength is controlled by active mode locking employing cross-gain modulation using the modulation light. The pulse width of the modulation light has a duration shorter than a duration of a half period of a driving signal for generating the modulation light.

Abstract: An optical network component is provided comprising a semiconductor optical amplifier with an input and an output, wherein the input is connected to a light source, wherein the output is connected to an amplitude modulator, wherein the semiconductor optical amplifier converts an amplitude modulated signal from the amplitude modulator to a phase modulated signal and provides the phase modulated signal at its output. Also, a transmitter comprising at least one such optical network component is suggested.

Abstract: An optical amplifier on a silicon platform includes a first doped device layer and a second doped device layer. A gain medium is positioned between the first and second doped device layers. The gain medium comprises extrinsic gain materials so as to substantially confine in the gain medium a light signal and allow the optical amplifier to be electrically or optically pumped.

Abstract: [Problems] To accommodate a plurality of optical semiconductor elements in one package with their optical axes aligned highly precisely. [Means for Solving the Problems] An optical transmission module includes an optical transmission unit, a carrier to become a base, a semiconductor optical amplification element mounted on the carrier through a first sub-carrier, first and second lenses fixed on the carrier through first and second lens holders, an element supporting member and an optical isolator fixed on the carrier, a third lens holder supported by the element supporting member, a third lens and a small carrier individually fixed in the third lens holder, and a semiconductor laser element mounted on the small carrier through a second sub-carrier.

Abstract: Provided are a meta-material and a method of fabricating the same. the metal-material may include a substrate, a metal layer on the substrate, and an active gain medium layer on the metal layer. The active gain medium layer and the metal layer may be configured to define hole patterns that may be periodically arranged to have a space smaller than a wavelength of an ultraviolet light, such that the active gain medium layer and the metal layer exhibit a negative refractive index in a wavelength region of the ultraviolet light.

Abstract: A method is provided for all-optical regeneration of intensity modulated optical signals. A DFB laser diode is selected such that it has a gain bandwidth comprising the signal wavelength, the signal wavelength being outside the stopband of the DFB laser diode. Furthermore, the DFB laser diode is selected such that it can have a bistable amplification characteristic for the signal wavelength showing a hysteresis with an ascending branch and a descending branch, the ascending branch located at a higher input power level than the descending branch. The DFB laser diode is driven such that it operates in the bistable amplification regime, the descending branch of the hysteresis curve located at an input power level above the lower power level of the optical signal pulses and the ascending branch of the hysteresis curve located at an input power level below the upper power level of the optical signal pulses.

Abstract: An optical amplifier includes a passive waveguide region and an active waveguide region. The passive waveguide region is configured to receive an incident optical signal and adjust a mode of the optical signal. The active waveguide region is integrated to the passive waveguide region and configured to perform gain modulation on the optical signal received from the passive waveguide region by changing density of carriers in response to a current applied to the active waveguide region. Internal loss of the active waveguide region is adjusted to produce a resonance effect and thereby to increase bandwidth of the active waveguide. Therefore, the optical amplifier can have a wide bandwidth under a low-current condition.

Abstract: A method for manufacturing an optically pumped surface-emitting semiconductor laser device, wherein a surface-emitting semiconductor laser layer sequence having a quantum confinement structure is applied onto a common substrate. The surface-emitting semiconductor laser layer sequence outside an intended laser region is removed and a region is exposed. An edge-emitting semiconductor layer sequence is applied onto the exposed region over the common substrate, wherein the exposed region is exposed via the removing step, and the exposed region is suitable for transmitting pump radiation into the quantum confinement structure. A current injection path is then formed in the edge-emitting semiconductor layer sequence.

Abstract: The invention relates to pulsed optical sources formed of a source of seed optical radiation, a pulsed optical amplifier for pulsing the seed optical radiation, and an output optical port for outputting a pulsed optical signal produced by the pulsed optical amplifier. An optically isolating element such as an optical circulator is provided in the optical path between the optical seed source and the pulsed optical amplifier.

Abstract: In an embodiment, a laser chip includes a laser, an optical amplifier, a first electrode, and a second electrode. The laser includes an active region. The optical amplifier is integrated in the laser chip in front of and in optical communication with the laser. The first electrode is electrically coupled to the active region. The second electrode is electrically coupled to the optical amplifier. The first electrode and the second electrode are configured to be electrically coupled to a common direct modulation source.

Abstract: A semiconductor optical amplifier module may include a beam splitter to split an optical signal into two polarization optical signals including a first polarization optical signal with a Transverse Magnetic (TM) polarization provided along a first path of two paths, and a second polarization optical signal with a Transverse Electric (TE) polarization provided along a second path of the two paths; a first rotator to rotate the TM polarization of the first polarization optical signal to TE polarization; a first semiconductor optical amplifier to amplify the rotated first polarization optical signal to output a first resultant optical signal; a second semiconductor optical amplifier to amplify the second polarization optical signal; and a second rotator to rotate the polarization of the amplified second polarization optical signal to output a second resultant optical signal; and a beam combiner to combine the first resultant optical signal and the second resultant optical signal.

Abstract: An optical amplifier includes a semiconductor optical amplifier, a power monitor configured to monitor an optical power of out-of-signal-band noise output from the semiconductor optical amplifier, and a corrector configured to correct a relationship between a driving current for the semiconductor optical amplifier and a noise optical power based on the out-of-signal-band noise optical power monitored by the first power monitor.

Abstract: The present invention relates to a device and a method for selective transmission of an optical signal. It is an object of the present invention to provide a light modulator and a method for light modulation capable of selecting very short optical pulses of up to the femtosecond range with a low repetition frequency, wherein the repetition frequency can be variable in a range between several Hz up to the GHz range. To this end, the device has a first optical waveguide (3), a first drive circuit (14), a second optical waveguide (1, 2) and a second drive circuit (15), wherein the spacing between a switching element of the first drive circuit (14) and the first optical waveguide (3) is less than 3 mm, and the distance between a switching element of the second drive circuit (15) and the second optical waveguide (1, 2) is less than 3 mm, and the first optical waveguide (3) has a first absorber section (5), a pulse picker section (4) and a second absorber section (18).

Abstract: A light amplifier includes a single crystal semiconductor substrate with a rare earth oxide, light amplifying gain medium deposited on the substrate and formed into a light waveguide, and a pump laser. A lattice matching virtual substrate integrates the pump laser to the gain medium with a first opposed surface crystal lattice matched to the gain medium and second opposed surface crystal lattice matched to the pump laser. The pump laser is positioned with a light output surface coupled to a light input surface of the gain medium so as to introduce pump energy into the light waveguide. The light amplifier has a very small footprint and allows the integration of control and monitoring electronics.

Abstract: A manufacturing method for an optical semiconductor device, including disposing a semiconductor element that has a polarization dependent gain or polarization dependent loss between optical waveguide modes differing in the direction of polarization, positioning a lens at one end face side of the semiconductor element based on an optical coupling loss between the lens and the semiconductor element, and repositioning the lens based on the polarization dependent gain or the polarization dependent loss of the semiconductor element.

Abstract: It is desirable to provide a semiconductor optical amplifier from which it becomes able to obtain a higher output power. A semiconductor optical amplifier in comprises an active wave guiding layer which comprises a passive core region that is formed of a semiconductor, and active cladding regions that are located at both sides of the passive core region and each of that is comprised of an active layer which is formed of a semiconductor and which has an index of refraction to be lower than that of the passive core region, wherein a light is wave guided with being amplified in the active wave guiding layer. Moreover, it is desirable for the active wave guiding layer to be formed of a compound semiconductor, and to be formed by integrating the passive core region and the active cladding regions to be monolithic on to a substrate that is formed of a compound semiconductor by making use of a process of a butt joint growth.

Abstract: The present invention relates to semiconductor devices comprising rare earth based optical gain medium layers suitable for electronic and optoelectronic applications.

Abstract: A laser device having a semiconductor gain element optically coupled to an optical fiber by using an angled anamorphic fiber lens and including a wavelength-selective front reflector. The laser device possesses improved output characteristics such as a highly linear laser emission output, even when the amplification section produces a high amount of gain. Such a laser source can also be used in various applications such as pump lasers for fiber amplifiers or frequency doubling systems.