Abstract: A nitride semiconductor laser diode includes a substrate, an n-side nitride semiconductor layer formed on the substrate, an active layer formed on the n-side nitride semiconductor layer and having a light emitting layer including InxAlyGa1?x?yN (0<x<1, 0 y<1, 0<x+y<1), and a p-side nitride semiconductor layer formed on the active layer.
Abstract: The present invention provides a semiconductor laser realizing reduced possibility that a wiring layer disposed in the air is broken even under severe environment of a large temperature difference. A trench is provided between adjacent ridges, and a wiring layer electrically connecting an upper electrode and a pad electrode is disposed in the air at least above the trench. The wiring layer in a portion above the trench has a flat shape or a concave shape which dents toward the trench. With the configuration, accumulation of strains in the wiring layer when the wiring layer repeats expansion and shrink under severe environment of a large temperature difference is suppressed.
Type:
Grant
Filed:
September 23, 2010
Date of Patent:
July 17, 2012
Assignee:
Sony Corporation
Inventors:
Hisayoshi Kuramochi, Tomonori Hino, Tatsuhiro Hirata, Yuta Yoshida
Abstract: The invention relates to a semiconductor laser having at least one semiconductor substrate (10), at least one active layer (20) arranged on the semiconductor substrate (10) which generates radiation in a wavelength region, at least one laser mirror (40) which is applied at one end of the active layer (20) perpendicular thereto, through which a part of the radiation generated in the active layer (20) emerges, and which is provided with a layer of absorbing material (50, 60) said layer being suitable for reducing a gradient of the luminous-power/current characteristic for radiation emerging through the laser mirror (40).
Abstract: A semiconductor laser module includes: a semiconductor laser element which emits light; a package base having a through hole; a lead pin which passes through the through hole and supplies the current to the semiconductor laser element; a glass material which seals the through hole through which the lead pin passes; and a cap which has a window from which light emitted by the semiconductor laser element is taken out and has the semiconductor laser element in the inside thereof, the cap being joined in air sealing relation to the package base. The lead pin is an iron-nickel alloys in which the coefficient of linear expansion is not higher than a predetermined ratio in difference with the glass material, the saturation magneto-striction constant is not higher than a predetermined value, and volume resistivity is not higher than a predetermined rate.
Abstract: Provided is a semiconductor laser including: a substrate (semiconductor substrate); an optical waveguide (active layer waveguide) with a mesa structure that includes an active layer (strain-compensated multiple quantum well active layer) including Al, is provided over the semiconductor substrate; a semiconductor protective layer that is provided so as to cover the top and the side of a mesa of the active layer waveguide; a current block layer that is provided so as to embed the active layer waveguide and the semiconductor protective layer; and a clad layer (p-type InP clad layer) that is provided over the semiconductor protective layer and the current block layer, wherein, the semiconductor protective layer has a semiconductor layer (p-type InGaAsP protective layer) that includes As, but does not include Al.
Abstract: Injection emitters (light-emitting diodes, superluminescent emitters) are used in the form of highly-efficient solid state radiation sources within a large wavelength range and for wide field of application, including general illumination using white light emitters provided with light-emitting diodes. Said invention also relates to superpower highly-efficient and reliable injection surface-emitting lasers, which generate radiation in the form of a plurality of output beams and which are characterized by a novel original and efficient method for emitting the radiation through the external surfaces thereof.
Abstract: An electrical device includes a charge carrier transport layer formed using a ternary semiconducting compound having a stoichiometry of 1:1:1 and an element combination selected from the set of I-II-V, I-III-IV, II-II-IV, and I-I-VI; or having a stoichiometry of 3:1:2 and an element combination selected from the set of I-III-V; or having a stoichiometry of 2:1:1 and an element combination selected from the set of I-II-IV. In some embodiments, the charge carrier transport layer is used as the radiation absorption layer for a photovoltaic cell, or a light emitting layer of a light emitting device. Other devices, such as laser diode, a photodetection device, an optical modulator, a transparent electrode and a window layer, can also be formed using the ternary semiconducting compound as the charge carrier transport.
Type:
Application
Filed:
November 17, 2011
Publication date:
May 24, 2012
Applicant:
The Board of Trustees of the Leland Stanford Junior University
Abstract: A semiconductor optical element has an active layer including quantum dots. The density of quantum dots in the resonator direction in a portion of the active layer in which the density of photons is relatively high is increased relative to the density of quantum dots in a portion of the active layer in which the density of photons is relatively low.
Abstract: A semiconductor laser is embodied as a surface emitting thin-film semiconductor laser (2) with a semiconductor body (4). The semiconductor body (4) comprises a first and a second planar surface (12, 14). The semiconductor body (4) comprises between the planar surfaces at least one active layer (10) for generating radiation. The semiconductor body (4) has, for coupling out the radiation from the active layer (10) toward the first planar surface (12), at least one first mirror area (26) inclined with respect to the active layer (10).
Abstract: A laser diode which realizes NFP with a stable and uniform shape. The laser diode includes, on a semiconductor substrate, an active layer, one or a plurality of strip-shaped current confinement structures confining a current which is injected into the active layer, and a stacked structure including one or a plurality of strip-shaped convex portions extending in an extending direction of the current confinement structure.
Abstract: A method of manufacturing a semiconductor optical device including a semiconductor layer includes: forming a semiconductor layer; forming a first dielectric film on a first region of a surface of the semiconductor layer; forming a second dielectric film on a second region of the surface of the semiconductor layer, the second dielectric film having a density higher than that of the first dielectric film; and performing a thermal treatment in a predetermined temperature range after the second dielectric film forming, wherein within the temperature range, as the temperature is lowered, a difference increases between a bandgap in the semiconductor layer below the second dielectric film and a bandgap in the semiconductor layer below the first dielectric film due to the thermal treatment.
Abstract: A method of fabricating group-III nitride semiconductor laser device includes: preparing a substrate comprising a hexagonal group-III nitride semiconductor and having a semipolar principal surface; forming a substrate product having a laser structure, an anode electrode, and a cathode electrode, where the laser structure includes a semiconductor region and the substrate, where the semiconductor region is formed on the semipolar principal surface; scribing a first surface of the substrate product in a direction of an a-axis of the hexagonal group-III nitride semiconductor to form first and second scribed grooves; and carrying out breakup of the substrate product by press against a second surface of the substrate product, to form another substrate product and a laser bar.
Abstract: A semiconductor laser module having a substrate and having at least one semiconductor laser situated on the substrate, the substrate having a layer structure which includes at least one primary layer which establishes a thermal contact with the semiconductor laser. The semiconductor laser is designed in such a way that it emits heat pulses having a minimum specific heat of approximately 3 mJ per mm2, preferably approximately 5 mJ/mm2, and having a pulse duration of approximately 100 ?s to approximately 2,000 ?s, and the primary layer has a layer thickness which is between approximately 200 ?m and approximately 2,000 ?m, preferably between approximately 400 ?m and approximately 2,000 ?m.
Type:
Application
Filed:
May 18, 2010
Publication date:
May 3, 2012
Inventors:
Werner Herden, Hans-Jochen Schwarz, Wolfgang Pittroff
Abstract: This nitride-based semiconductor laser element includes a semiconductor element layer made of a nitride-based semiconductor having an emitting-side cavity facet and a reflecting-side cavity facet, and a facet coating film formed on the emitting-side cavity facet. The facet coating film has a first dielectric film made of aluminum nitride formed in contact with the emitting-side cavity facet, a second dielectric film made of aluminum oxynitride formed on a side of the first dielectric film opposite to the emitting-side cavity facet, a third dielectric film made of aluminum oxide formed on a side of the second dielectric film opposite to the first dielectric film, a fourth dielectric film made of aluminum oxynitride formed on a side of the third dielectric film opposite to the second dielectric film, and a fifth dielectric film made of aluminum oxide formed on a side of the fourth dielectric film opposite to the third dielectric film.
Abstract: An photonic device, comprising one section of a material which is different from the material of another section such that the two sections present different optical birefringent index values. This causes a first set of polarization modes to move in a spectral space with a different velocity than a second set of polarization modes. A bias current, or voltage, is used for controlling the overall birefringence effect in the device. The biasing for controlling the birefringence effect is performed such the TE modes and the TM modes of the device are made to coincide in their respective spectral position. Thus the device is made insensitive, or presents substantially reduced sensitivity, to the polarization of any incoming optical signal.
Abstract: A semiconductor laser diode apparatus capable of suppressing variation in an emission position and an emission direction of a laser beam emitted from a semiconductor laser diode element is obtained. This semiconductor laser diode apparatus includes a semiconductor laser diode element having warping along either a first direction in which a cavity extends or a second direction intersecting with the first direction and a base on which a convex side of the warping of the semiconductor laser diode element is fixed, wherein a distance between a first end of the semiconductor laser diode element in a direction of larger warping among the first and second directions and the base is smaller than a distance between a second end of the semiconductor laser diode element in the direction of the large warping among the first and second directions and the base.
Abstract: A quantum cascade laser (QCL) having a bias-neutral design and a semiconductor with multiple layers of AlxIn1-xAs/InyGa1-yAs. The first active region barrier has a thickness of less than fourteen angstroms, and the second active region barrier has a thickness of less than eleven angstroms. The lower active region wavefunction overlaps with each of the injector level wavefunctions. Also, the laser transition is vertical at a bias close to roll-over. The injector level 3? is above a lower laser level 3, the injector level 2? is below the lower laser level 3, and the active region level 2 is confined to the active region. The lower laser level 3 is separated from the active region level 2 by the energy of the LO phonon. The remaining active region states and the remaining injector states are either above the lower laser level 3 or significantly below the active region level 2.
Type:
Grant
Filed:
December 22, 2010
Date of Patent:
February 21, 2012
Assignee:
Pranalytica, Inc.
Inventors:
Arkadiy Lyakh, Richard Maulini, Alexei Tsekoun, C. Kumar N. Patel
Abstract: A Quantum Cascade (QC) structure(s) for use in Quantum Cascade Lasers (QCLs) that use step quantum well(s) in which the radiative and LO-phonon transitions are both vertical transitions and within the same step well. This approach allows for a high oscillator strength and uses LO-phonon scattering for fast depopulation of the middle state (lower lasing state) for maintaining a population inversion. The step also reduces unwanted injection into the lower lasing state due to spatial separation of the wavefunctions. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. This Abstract is submitted with the understanding that it will not be used to interpret or limit the scope of the claims.
Type:
Grant
Filed:
September 8, 2009
Date of Patent:
January 17, 2012
Assignee:
United States of America as represented by the Secretary of the Navy
Abstract: A laser system employing amplification via a single exciton regime and to optical gain media having single exciton amplification is provided.
Abstract: A laser diode with an improved kink level in the L-I characteristic and capable of obtaining a stable high output in a horizontal transverse mode is provided. The laser diode includes an active layer made of nitride III-V compound semiconductor containing at least gallium (Ga) in 3B-group elements and at least nitrogen (N) in 5B-group elements, an n-type compound semiconductor layer provided on one of faces of the active layer, and a p-type compound semiconductor layer provided on the other face of the active layer. A region closest to the active layer, in the n-type compound semiconductor layer is a high-concentration region whose impurity concentration is higher than that of the other n-type regions.
Abstract: The laser device has a gain medium, first and second clads sandwiching the gain medium in the thickness direction, and a cavity structure for resonating the electromagnetic wave generated in the gain medium. The gain medium includes a plurality of active regions for generating an electromagnetic wave and at lease one connecting region sandwiched among the active regions. The first and second clads are each formed of a negative permittivity medium having a permittivity the real part of which is negative relative to the electromagnetic wave. A potential-adjusting portion is arranged between the connecting region and the first clad and between the connecting region and the second clad for adjusting the electric potential of the connecting region.
Abstract: A surface emitting laser element includes a light emission part having a mesa structure. The light emission part includes a lower reflector; a resonator structure including an active layer; and an upper reflector. The lower reflector, the resonator structure and the upper reflector are laminated on a substrate. A peripheral part of a top surface of the mesa structure is covered by a dielectric layer that has a tapered surface such that a thickness decreases in a direction toward an outermost part, a taper angle of the tapered surface with respect to a surface of the substrate is smaller than a slope angle of a side wall of the mesa structure with respect to the surface of the substrate, and an end part of the dielectric layer coincides with an end part of the upper reflector.
Abstract: A new broadband source having a discrete set of spectral emission lines having high peak power in each line is provided by placing a gain medium in a reflective cavity comprising reflective front and back surfaces. A cavity feedback factor less than unity is achieved by providing reflectivity of one surface substantially lower than the reflectivity of the other surface such that spontaneous emission in the gain medium is linearly amplified just below the lasing threshold. In an alternative arrangement, a movable external back surface placed at a prescribed distance from the gain medium provides a means to achieve a free spectral range and finesse of the emission lines to match a pitch of a detector array in a SD-OCT system. By simultaneously providing high power to each detector element of the array, sensitivity and imaging speed of SD-OCT system are significantly improved.
Abstract: A semiconductor optical element has an active layer including quantum dots. The density of quantum dots in the resonator direction in a portion of the active layer in which the density of photons is relatively high is increased relative to the density of quantum dots in a portion of the active layer in which the density of photons is relatively low.
Abstract: A quantum cascade laser includes a semiconductor substrate, and an active layer which is provided on the semiconductor substrate, and has a cascade structure in which unit laminate structures 16 having quantum well emission layers 17 and injection layers 18 are laminated in multiple stages. Further, the quantum cascade laser is configured such that the unit laminate structure 16 has an emission upper level Lup, an emission lower level Llow, and a relaxation miniband MB including an energy level lower than the emission lower level in its subband level structure, and light is generated by an intersubband transition of electrons from the upper level to the lower level, and the electrons after the intersubband transition are relaxed from the lower level Llow to the miniband MB through LO phonon scattering, to be injected from the injection layer 18 to the latter stage emission layer via the miniband MB.
Abstract: In an integrated semiconductor optical device, a first cladding layer is made of a first conductivity type semiconductor. A first active layer for forming a first semiconductor optical device is provided on the first cladding layer in a first area of a principal surface of a substrate. A second active layer for forming a second semiconductor optical device is provided on the first cladding layer in a second area of the principal surface. A second cladding layer made of a second conductivity type semiconductor is provided on the second active layer. A third cladding layer made of a first conductivity type semiconductor is provided on the first active layer. A tunnel junction region is provided between the first active layer and the third cladding layer. The first active layer is coupled to the second active layer by butt joint. The second and third cladding layers form a p-n junction.
Abstract: This semiconductor laser apparatus includes a semiconductor laser chip and a package sealing the semiconductor laser chip. The package includes a base body made of resin, a first sealing member mounted on an upper surface of the base body and a translucent second sealing member mounted on a front surface of the base body. The base body has an opening passing through the base body from the upper surface to the front surface, and the side of the opening closer to the upper surface is sealed with the first sealing member, while the side of the opening closer to the front surface is sealed with the second sealing member.
Abstract: A semiconductor laser element includes a first electrode, a second electrode, a first reflecting mirror, a second reflecting mirror, and a resonator. The resonator includes an active layer, a current confinement layer, a first semiconductor layer having a first doping concentration formed at a side opposite to the active layer across the current confinement layer, and a second semiconductor layer having a second doping concentration higher than the first doping concentration formed between the first semiconductor layer and the current confinement layer. The first electrode is provided to contact a part of a surface of the first semiconductor layer. The first semiconductor layer has a diffusion portion into which a component of the first electrode diffuses. The second semiconductor layer contacts the diffusion portion. The second semiconductor layer is positioned at a node of a standing wave at a time of laser oscillation of the semiconductor laser element.
Abstract: An optoelectronic semiconductor chip having a semiconductor layer sequence with a plurality of layers arranged over one another includes an active layer with an active region which emits electromagnetic radiation in an emission direction when in operation, a first grating layer on the active layer which, in an emission direction, has a plurality of stripes in the form of grating lines extending perpendicularly to the emission direction with spaces arranged therebetween, and a second grating layer on the first grating layer which covers the stripes of the first grating layer and the spaces and which comprises a transparent material applied by non-epitaxial application.
Abstract: A disclosed surface-emitting laser module includes a surface-emitting laser formed on a substrate to emit light perpendicular to its surface, a package including a recess portion in which the substrate having the surface-emitting laser is arranged, and a transparent substrate arranged to cover the recess portion of the package and the substrate having the surface-emitting laser such that the transparent substrate and the package are connected on a light emitting side of the surface-emitting laser. In the surface-emitting laser module, a high reflectance region and a low reflectance region are formed within a region enclosed by an electrode on an upper part of a mesa of the surface-emitting laser, and the transparent substrate is slanted to the surface of the substrate having the surface-emitting laser in a polarization direction of the light emitted from the surface-emitting laser determined by the high reflectance region and the low reflectance region.
Abstract: A quantum cascade laser utilizing non-resonant extraction design having a multilayered semiconductor with a single type of carrier; at least two final levels (1 and 1?) for a transition down from level 2; an energy spacing E21 greater than ELO; an energy spacing E31 of about 100 meV; and an energy spacing E32 about equal to ELO. The carrier wave function for level 1 overlaps with the carrier wave function for level 2. Likewise, the carrier wave function for level 1? overlaps with the carrier wave function for level 2. In a second version, the basic design also has an energy spacing E54 of about 90 meV, and levels 1 and 1? do not have to be spatially close to each other, provided that level 2 has significant overlap with both these levels. In a third version, there are at least three final levels (1, 1?, and 1?) for a transition down from level 2. Each of the levels 1, 1?, and 1? has a non-uniform squared wave function distribution.
Type:
Grant
Filed:
February 27, 2009
Date of Patent:
September 6, 2011
Assignee:
President and Fellows of Harvard College
Inventors:
C. Kumar N. Patel, Alexei Tsekoun, Richard Maulini, Arkadiy Lyakh, Christian Pflugl, Laurent Diehl, Qijie Wang, Federico Capasso
Abstract: A manufacturing method for manufacturing a surface-emitting laser device includes the steps of forming a laminated body in which a lower reflecting mirror, a resonator structure including an active layer, and an upper reflecting layer having a selective oxidized layer are laminated on a substrate; etching the laminated body to form a mesa structure having the selective oxidized layer exposed at side surfaces thereof; selectively oxidizing the selective oxidized layer from the side surfaces of the mesa structure to form a constriction structure in which a current passing region is surrounded by an oxide; forming a separating groove at a position away from the mesa structure; passivating an outermost front surface of at least a part of the laminated body exposed when the separating groove is formed; and coating a passivated part with a dielectric body.
Abstract: A semiconductor ring laser (SRL) section is monolithically integrated with a DFB or DBR master laser section on a semiconductor substrate of a light-emitting device to provide an injection locking mode of operation that can result in low-cost ultrafast (over 100 GHz) functional chip that will be easy to use in practice.
Type:
Grant
Filed:
July 24, 2009
Date of Patent:
August 30, 2011
Assignee:
STC.UNM
Inventors:
Marek A. Osinski, Omar K. Qassim, Nathan J. Withers, Gennady A. Smolyakov
Abstract: A photonic device incorporates an epitaxial structure having an active region, and which includes a wet etch stop layer above, but close to, the active region. An etched-facet ridge laser is fabricated on the epitaxial structure by dry etching followed by wet etching. The dry etch is designed to stop before reading the depth needed to form the ridge. The wet etch completes the formation of the ridge and stops at the wet etch stop layer.
Type:
Grant
Filed:
September 25, 2009
Date of Patent:
August 30, 2011
Assignee:
Binoptics Corporation
Inventors:
Alex A. Behfar, Alfred T. Schremer, Cristian B. Stagarescu
Abstract: A side emitting semiconductor package includes a two-sided electric circuit formed on a silicon substrate of the package, and a plurality of semiconductor light emitting devices bonded on two bilateral surfaces of the electric circuit to provide a surface mounted device with two light emitting sides.
Type:
Application
Filed:
October 8, 2010
Publication date:
August 25, 2011
Applicant:
ADVANCED OPTOELECTRONIC TECHNOLOGY, INC.
Inventors:
MIN-TSUN HSIEH, WEN-LIANG TSENG, LUNG-HSIN CHEN, CHIH-YUNG LIN
Abstract: A semiconductor laser outputs a laser light from an output facet of a waveguide having an index waveguide structure, via a lens system. The waveguide includes, in order from a rear facet opposite to the output facet, a first narrow portion, a wide portion that is wider than the first narrow portion, a second narrow portion narrower than the wide portion, a first tapered portion formed between the first narrow portion and the wide portion, which expands toward the wide portion, and a second tapered portion formed between the wide portion and the second narrow portion, which narrows toward the second narrow portion. Each of the first narrow portion, the wide portion, and the second narrow potion has a uniform width.
Abstract: A method for producing wide bandwidth laser emission responsive to high frequency electrical input signals, including the following steps: providing a heterojunction bipolar transistor device having collector, base, and emitter regions; providing at least one quantum size region in the base region, and enclosing at least a portion of the base region in an optical resonant cavity; coupling electrical signals, including the high frequency electrical input signals, with respect to the collector, base and emitter region, to cause laser emission from the transistor device; and reducing the operating beta of the transistor laser device to enhance the optical bandwidth of the laser emission in response to the high frequency electrical signals.
Type:
Grant
Filed:
October 14, 2009
Date of Patent:
August 23, 2011
Assignee:
The Board of Trustees of the University of Illinois
Inventors:
Han Wui Then, Gabriel Walter, Milton Feng, Nick Holonyak, Jr.
Abstract: An optical device includes: an optical element having a first light-emitting region in the vicinity of a first surface and a first metal layer in contact with at least a region of the first surface which does not face the first light-emitting region; a support body disposed on the side of the optical element toward which the first surface faces; and a fuse-bonding layer disposed between the first surface and the support body and in a region which does not face the first light-emitting region, the fuse-bonding layer bonding the first metal layer and the support body.
Abstract: A semiconductor laser device includes a multilayer structure made of group III nitride semiconductors formed on a substrate. The multilayer structure includes a MQW active layer, and also includes a step region selectively formed in an upper portion thereof. In another upper portion of the multilayer structure, a ridge stripe portion including a waveguide, which extends in parallel to a principal surface of the multilayer structure, is formed. In the vicinity of the step region, a first region, in which the MQW active layer has a bandgap energy of Eg1, is formed, and a second region, which is adjacent to the first region and in which the MQW active layer has a bandgap energy of Eg2 (Eg2<Eg1), is formed. The waveguide, which is formed so as to include the first and second regions and so as not to include the step region, performs self-oscillation.
Abstract: The present invention provides a nitride semiconductor light emitting device having an n-type ohmic electrode with an Au face excellent in ohmic contacts and in mounting properties, and a method of manufacturing the same. The device uses an n-type ohmic electrode having a laminate structure that is composed of: a first layer containing Al as a main ingredient and having a thickness not greater than 10 nm or not less than 3 nm; a second layer containing one or more metals selected from Mo and Nb, so as to suppress the upward diffusion of Al; a third layer containing one or more metals selected from Ti and Pt, to suppress the downward diffusion of Al; and a fourth layer being made of Au, from the side in contact with an n-type nitride substrate in order of mention, and after the laminate structure is formed, the n-type ohmic electrode is annealed.
Abstract: Carbon nanotube (CNT)-based devices and technology for their fabrication are disclosed. The planar, multiple layer deposition technique and simple methods of change of the nanotube conductivity type during the device processing are utilized to provide a simple and cost effective technology for large scale circuit integration. Such devices as p-n diode, CMOS-like circuit, bipolar transistor, light emitting diode and laser are disclosed, all of them are expected to have superior performance then their semiconductor-based counterparts due to excellent CNT electrical and optical properties. When fabricated on semiconductor wafers, the CNT-based devices can be combined with the conventional semiconductor circuit elements, thus producing hybrid devices and circuits.
Abstract: A laser light source comprises, in particular, a semiconductor layer sequence (10) having an active region (45) and a radiation coupling-out area (12) having a first partial region (121) and a second partial region (122) different than the latter, and a filter structure (5), wherein the active region (45) generates, during operation, coherent first electromagnetic radiation (51) having a first wavelength range and incoherent second electromagnetic radiation (52) having a second wavelength range, the coherent first electromagnetic radiation (51) is emitted by the first partial region (121) along an emission direction (90), the incoherent second electromagnetic radiation (52) is emitted by the first partial region (121) and by the second partial region (122), the second wavelength range comprises the first wavelength range, and the filter structure (5) at least partly attenuates the incoherent second electromagnetic radiation (52) emitted by the active region along the emission direction (90).
Type:
Application
Filed:
December 17, 2008
Publication date:
August 4, 2011
Applicant:
OSRAM Opto Semiconductors GmbH
Inventors:
Alfred Lell, Christoph Eichler, Wolfgang Schmid, Soenke Tautz, Wolfgang Reill, Dimitri Dini
Abstract: A multi-band (multi-color) multiwavelength mode locked laser diode is provided by dynamic phase compensation of a quantum dot active medium. The laser diode is provided with a PIN diode structure where the active medium consists of a plurality of layers of quantum dots such as those produced by self-assembly from known chemical beam epitaxy methods. The multiplicity of bands may be produced by AC Stark splitting, frequency selective attenuation, or by the inclusion of multiple different layers having different, respective, peak ASE emissions. Dispersion compensation within laser facets, waveguides, and the optically active media permit the selection of a fixed dispersion within the cavity. A dynamic group phase change induced by the AC Stark effect permits compensation of the fixed dispersion sufficiently to produce an intraband mode-locked laser. Even interband mode locking was observed.
Type:
Grant
Filed:
September 25, 2009
Date of Patent:
August 2, 2011
Assignee:
National Research Council of Canada
Inventors:
Jiaren Liu, Zhenguo Lu, Sylvain Raymond, Philip Poole, Pedro Barrios, Daniel Poitras
Abstract: A nitride semiconductor laser diode includes a second conductive cladding layer formed on an active layer, and including a ridge portion having a raised cross-sectional shape, and flat portions located on both sides of the ridge portion; a light-absorbing layer formed on each of the flat portions, and having an optical absorption coefficient larger than the second conductive cladding layer. The light-absorbing layer includes a first region provided at a side of a light-emitting facet, and having a distance Di1 from a line-symmetric axis in a longitudinal direction of the ridge portion to a side surface of the light-absorbing layer; and a second region provided at a side opposite to the light-emitting facet, and having a distance Di2 from the line-symmetric axis to the side surface of the light-absorbing layer. A relationship between the Di1 and the Di2 is represented by Di1<Di2.
Abstract: A semipolar {20-21} III-nitride based laser diode employing a cavity with one or more etched facet mirrors. The etched facet mirrors provide an ability to arbitrarily control the orientation and dimensions of the cavity or stripe of the laser diode, thereby enabling control of electrical and optical properties of the laser diode.
Type:
Application
Filed:
October 20, 2010
Publication date:
July 14, 2011
Applicant:
THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
Inventors:
Anurag Tyagi, Robert M. Farrell, Chia-Yen Huang, Po Shan Hsu, Daniel A. Haeger, Kathryn M. Kelchner, Hiroaki Ohta, Shuji Nakamura, Steven P. DenBaars, James S. Speck
Abstract: A laser diode is configured with a substrate delimited by opposite AR and HR reflectors and a gain region. The gain region bridges the portions of the respective AR and HR reflectors and is configured with a main resonant cavity and at least one side resonant cavity. The main resonant cavity spans between the portions of the respective reflectors, and at least one additional resonant cavity extends adjacent to the main resonator cavity. The gain region is configured so that stimulated emission is generated only the main resonant cavity. Accordingly, the laser diode is operative to radiate a high-power output beam emitted through the portion of the AR reflector which is dimensioned to shape the output beam with the desired near-field.
Type:
Application
Filed:
December 30, 2009
Publication date:
June 30, 2011
Applicant:
IPG Photonics Corporation
Inventors:
Valentin P. Gapontsev, Alexander Ovtchinnikov, Alexey Komissarov, Pavel Trubenko
Abstract: A laser diode device with which a low voltage is realized is provided. The laser diode device includes: a substrate; a semiconductor laminated structure including a first conductive cladding layer, an active layer, and a second conductive cladding layer on one face side of the substrate and having a contact layer as the uppermost layer, in which a protrusion is formed in the contact layer and the second conductive cladding layer; and an electrode provided on the contact layer. The contact layer has a concavo-convex structure on a face on the electrode side, and the electrode is contacted with the contact layer at contact points of a top face, a side face, and a bottom face of the concavo-convex structure.
Abstract: An integrated semiconductor laser device capable of improving the properties of a laser beam and reducing the cost for optical axis adjustment is provided. This integrated semiconductor laser device comprises a first semiconductor laser element including a first emission region and having either a projecting portion or a recess portion and a second semiconductor laser element including a second emission region and having either a recess portion or a projecting portion. Either the projecting portion or the recess portion of the first semiconductor laser element is fitted to either the recess portion or the projecting portion of the second semiconductor laser element.
Abstract: Disclosed is a semiconductor laser in which the substrate comprises at least three independent functional sections in the direction of light wave propagation, said functional sections serving different functions and being individually triggered by means of electrodes via electrode leads. An intensification zone, a grid zone, and a phase adjustment zone are provided as functional sections. The light wave is optically intensified in the intensification zone while the phase of the advancing and returning wave is adjusted in the phase adjustment zone. The grid zone is used for selecting the wavelength and adjusting the intensity of coupling between the intensification zone and the phase adjustment zone.
Type:
Grant
Filed:
June 22, 2009
Date of Patent:
June 7, 2011
Assignee:
Nanoplus Nanosystems and Technologies GmbH
Inventors:
Johann Peter Reithmaier, Lars Bach, Wolfgang Kaiser
Abstract: An etched-facet single lateral mode semiconductor photonic device is fabricated by depositing an anti reflective coating on the etched facet, and depositing a reflectivity modifying coating in a spatially controlled manner to modify the spatial performance of the emitted beam.