| Patent Number |
Title Of Patent |
Date Issued |
| 7092421 |
Unipolar, intraband optoelectronic transducers with micro-cavity resonators |
August 15, 2006 |
| An optoelectronic transducer comprises a unipolar, intraband active region and a micro-cavity resonator. The resonator includes a 2D array of essentially equally spaced regions that exhibits resonant modes. Each of the spaced regions has a depth that extends through the active region and |
| 7010010 |
Broadband cascade light emitters |
March 7, 2006 |
| A broadband CLE capable of operation simultaneously at multiple wavelengths comprises: a core region including a multiplicity or cascade of stages, each stage including a radiative transition region. A first group of stages emits radiation at a first wavelength and at a first aggrega |
| 6940639 |
Phase matched parametric light generation in monolithically integrated intersubband optical devi |
September 6, 2005 |
| An optical device comprises a cavity resonator and an intracavity ridge waveguide. The ridge waveguide includes a monolithically integrated intersubband core region and a nonlinear mixing region (NMR). In response to external pumping energy the core region generates laser light at a |
| 6891187 |
Optical devices with heavily doped multiple quantum wells |
May 10, 2005 |
| A quantum well structure is provided that includes two or more quantum well layers coupled by at least one barrier layer such that at least one of a piezo-electric field and a pyro-electric field is produced. The quantum well structure is sufficiently doped to cause a Fermi energy to be |
| 6836499 |
Optical amplifier for quantum cascade laser |
December 28, 2004 |
| Techniques for amplifying light produced by a quantum cascade laser are described. An assembly according to the present invention includes an optical amplifier having an optical input and an optical output. The optical output has an area significantly greater than that of the optical |
| 6816530 |
Nonlinear semiconductor light sources |
November 9, 2004 |
| A monolithic apparatus has a laser optical cavity. The laser optical cavity has a multi-layer structure that includes a first active semiconductor multi-layer and a second semiconductor multi-layer. The second semiconductor multi-layer is located laterally adjacent to the first activ |
| 6795467 |
Technique for measuring intersubband electroluminescence in a quantum cascade laser |
September 21, 2004 |
| The measurement of intersubband electroluminescence (ISB-EL) in unipolar quantum cascade lasers is achieved by forming a longitudinal cleave through the active region and waveguide of the QC laser device, exposing a complete side face of the device, including the active region. The c |
| 6760354 |
Intersubband light emitters with injection/relaxation regions doped to different levels |
July 6, 2004 |
| In an intersubband light emitter, at least two injection/relaxation (I/R) regions contiguous with the same RT region have different doping levels. Preferably, one I/R region has a doping level that is at least 100 times lower than that of the other I/R region. In one embodiment, one I/R |
| 6728282 |
Engineering the gain/loss profile of intersubband optical devices having heterogeneous cascades |
April 27, 2004 |
| An optical device includes a stack of at least two different intersubband (ISB) optical sub-devices in which the gain/loss profiles of the individual ISB sub-devices are mutually adapted, or engineered, so as to generate a predetermined overall function for the combination. We define |
| 6690699 |
Quantum cascade laser with relaxation-stabilized injection |
February 10, 2004 |
| An optical gain medium has first and second active layers and an injector layer interposed between the first and second active layers. The active layers have upper minibands and lower minibands. The injector layer has a miniband that transports charge carriers from the lower miniband of |
| 6563852 |
Self-mode-locking quantum cascade laser |
May 13, 2003 |
| A self-mode-locking (SML) mid-infrared (5 and 8 .mu.m) quantum cascade laser is formed that comprises both a relatively thin dielectric insulating layer (i.e., less than one-half micron in thickness) overlaid with an optically highly lossy (i.e., absorbing) layer, with a relatively l |
| 6556604 |
Flat minibands with spatially symmetric wavefunctions in intersubband superlattice light emitter |
April 29, 2003 |
| The RT regions of an ISB light emitter comprise pre-biased SLs and a multiplicity of split quantum wells (SPQWs). A SPQW is a quantum well that is divided into a multiplicity of sub-wells by a first barrier layer sufficiently thin that the upper and lower energy states are split beyond |
| 6501783 |
Distributed feedback surface plasmon laser |
December 31, 2002 |
| A surface plasmon laser structure is formed to include a DFB structure as the metal carrying layer, thus forming a single mode surface plasmon laser. The DFB structure comprises a multiple layer metallic surface guiding structure (for example, titanium stripes covered with a layer of |
| 6463088 |
Mesa geometry semiconductor light emitter having chalcogenide dielectric coating |
October 8, 2002 |
| In a mesa geometry semiconductor laser, a patterned dielectric coating used to define the stripe geometry contact on the top the mesa and to provide significant waveguiding comprises a chalcogenide glass. Applications to intersubband (e.g., quantum cascade) lasers are specifically descri |
| 6400744 |
Apparatus comprising a quantum cascade laser having improved distributed feedback for single-mod |
June 4, 2002 |
| An article comprising a QC-DFB laser is disclosed. In the QC-DFB laser, an overlying grating structure achieves relatively strong coupling of the guided mode to the grating, and is thus highly effective in inducing single-mode operation even under cw operating conditions. The grating |
| 6333944 |
Semiconductor laser for operation in librational modes |
December 25, 2001 |
| A solid state laser comprises a cavity resonator in the form of a generally cylindrical body and, located within the resonator, an active region which generates lasing light when suitably pumped. The resonator has a relatively high effective refractive index (n>2 and typically n>3) |
| 6326646 |
Mounting technology for intersubband light emitters |
December 4, 2001 |
| A mounting technology that increases the cw operating temperature of intersubband lasers, without increasing the risk of hot spots near the facets and short circuits near the perimeter of the laser chip, is described. In accordance with one embodiment of our invention, a method of fa |
| 6324199 |
Intersubband light source with separate electron injector and reflector/extractor |
November 27, 2001 |
| An intersubband semiconductor light source comprises a core region that includes a unipolar, radiative transition (RT) region having upper and lower energy levels, an injector-only (I) region disposed on one side of the RT region, and a reflector/extractor-only (R/E) region disposed on t |
| 6301282 |
Long wavelength semiconductor lasers incorporating waveguides based on surface plasmons |
October 9, 2001 |
| A long wavelength (e.g., mid-IR to far-IR) semiconductor laser comprises an active region and at least one cladding region characterized in that the cladding region includes a light guiding interface between two materials which have dielectric constants opposite in sign. Consequently, th |
| 6278134 |
Bi-directional unipolar semiconductor light source |
August 21, 2001 |
| A bi-directional semiconductor light source is formed that provides emission in response to either a positive or negative bias voltage. In a preferred embodiment with an asymmetric injector region in a cascade structure, the device will emit at a first wavelength (.lambda..sup.-) und |
| 6271069 |
Method of making an article comprising an oxide layer on a GaAs-based semiconductor body |
August 7, 2001 |
| Disclosed are a method of making GaAs-based enhancement-type MOS-FETs, and articles (e.g., GaAs-based ICs) that comprise such a MOS-FET. The MOS-FETs are planar devices, without etched recess or epitaxial re-growth, with gate oxide that is primarily Ga.sub.2 O.sub.3, and with low midgap |
| 6265322 |
Selective growth process for group III-nitride-based semiconductors |
July 24, 2001 |
| A method of forming selected Group III-nitride regions uses a masking layer to cause differential growth between single crystal Group III-nitride material and polycrystalline Group III-nitride material. The epitaxial process is chosen to provide vertical growth so as to allow for rep |
| 6240114 |
Multi-quantum well lasers with selectively doped barriers |
May 29, 2001 |
| An MQW laser comprises an active region in which a multiplicity of barriers each includes a doped barrier layer separated from its adjacent quantum well layers by undoped barrier layers. In a preferred embodiment, each barrier of an InGaAsP/InP SCH MQW laser includes a p-type (e.g., Be, |
| 6180429 |
Process for selective area growth of III-V semiconductors |
January 30, 2001 |
| The specification describes a lift-off technique useful in the manufacture of III-V semiconductor devices such as MQW lasers. The lift-off step is improved by a spacer layer of III-V semiconductor that can be non-selectively etched to form a mesa stripe, and selectively etched for th |
| 6148012 |
Multiple wavelength quantum cascade light source |
November 14, 2000 |
| A multiple wavelength quantum cascade (QC) superlattice (SL) light source has at least three energy levels in each radiative transition (RT) region, and electron transitions between the levels give rise to emission lines at different wavelengths. In one embodiment, a lower miniband has a |
| 6144681 |
Article comprising a dual-wavelength quantum cascade photon source |
November 7, 2000 |
| The quantum cascade (QC) photon source according to this invention can emit simultaneously at two distinct wavelengths, typically both in the mid-infrared. This is accomplished through provision of a semiconductor layer structure in which, at the proper bias voltage, electrons are in |
| 6137817 |
Quantum cascade laser |
October 24, 2000 |
| A novel quantum cascade (QC) laser comprises a multiplicity of identical repeat units, with each repeat unit comprising an active region and an injector region. The injector region comprises quantum wells and barriers, selected to facilitate, under appropriate bias, resonant carrier tran |
| 6134257 |
Solid state laser for operation in librational modes |
October 17, 2000 |
| A solid state laser comprises a cavity resonator in the form of a generally cylindrical body and, located within the resonator, an active region which generates lasing light when suitably pumped. The resonator has a relatively high effective refractive index (n>2 and typically n>3) |
| 6110438 |
Method of making black phosphorus from red phosphorus |
August 29, 2000 |
| The specification describes a method for producing black phosphorus from red phosphorus by thermally cycling red phosphorus in a vacuum between 360-400.degree. C. and 200-240.degree. C., whereupon the red phosphorous undergoes an allotropic phase change to black phosphorus. |
| 6091753 |
Article comprising an improved superlattice quantum cascade laser |
July 18, 2000 |
| A novel superlattice quantum cascade (SLQC) laser has undoped SL active regions, with the dopant concentration in the injector region being selected, such that, under an appropriate electrical bias, the SL active region is substantially electric field free. The absence of dopant atoms |
| 6055257 |
Quantum cascade laser |
April 25, 2000 |
| A QC laser comprises first and second optical confinement (i.e., cladding) regions, and an In-based, Group III-V compound, QC active region disposed between the confinement regions. At least the first confinement region and the active region having the shape of an elongated mesa. An i-ty |
| 6055254 |
Quantum cascade light emitter with pre-biased internal electronic potential |
April 25, 2000 |
| Instead of trying to keep the SLs of a QC laser field free, we "pre-bias" the actual electronic potential by varying the SL period (and hence average composition) so as to achieve an essentially flat profile, on average, of upper and lower minibands, despite the presence of an applied |
| 6023482 |
Article comprising a strain-compensated QC laser |
February 8, 2000 |
| A quantum cascade (QC) laser has a multilayer core region comprising alternating layers of a first and a second semiconductor material, with lattice constants a.sub.1 and a.sub.2, respectively. The first material is selected such that a.sub.1 >a.sub.0, where a, is the lattice constant |
| 5978397 |
Article comprising an electric field-tunable semiconductor laser |
November 2, 1999 |
| In a novel tunable semiconductor laser, the lasing transition is a non-resonant tunneling transition, with the frequency of the emitted photon depending on the electrical bias across the multi-period active region of the laser. The laser can be designed to emit in the mid-IR, and can |
| 5936989 |
Quantum cascade laser |
August 10, 1999 |
| The core of the disclosed novel quantum cascade (QC) laser comprises a multiplicity of nominally identical repeat units, with a given repeat unit comprising a superlattice active region and a carrier injector region. Associated with the superlattice active region is an upper and a lower |
| 5903037 |
GaAs-based MOSFET, and method of making same |
May 11, 1999 |
| It has been found that a Ga-oxide-containing layer is substantially not etched in HF solution if the layer is a Ga-Gd-oxide with Gd:Ga atomic ratio of more than about 1:7.5, preferably more than 1:4 or even 1:2. This facilitates removal of a protective dielectric (typically SiO.sub.2) la |
| 5901168 |
Article comprising an improved QC laser |
May 4, 1999 |
| It has been found that previously known quantum cascade (QC) lasers have a shortcoming that substantially decreases their usefulness as radiation sources for pollution monitoring and other potential applications that involve absorption measurements. Except at cryogenic temperatures, thes |
| 5745516 |
Article comprising a unipolar superlattice laser |
April 28, 1998 |
| The novel unipolar laser resembles a quantum cascade laser but utilizes radiative transitions between upper and lower minibands of superlattices, with injection of charge carriers from the lower miniband into the upper miniband of the adjacent downstream superlattice facilitated by a |
| 5727012 |
Heterostructure laser |
March 10, 1998 |
| The specification describes a heterostructure laser utilizing GaAs based materials that emits at 0.98 .mu.m and is thus suitable for pumping an erbium doped fiber waveguide amplifier. The composition of the cladding layers of the laser is designed to give exceptional electrical and optic |
| 5727010 |
Article comprising an improved quantum cascade laser |
March 10, 1998 |
| The disclosed improved quantum cascade (QC) laser comprises features that facilitate lasing at temperatures above 260 K, preferably above 300 K. Among the features is a wavefunction-increasing feature that enhances the amplitude of the lasing level wavefunction in the adjacent upstream |
| 4111725 |
Selective lift-off technique for fabricating GaAs FETs |
September 5, 1978 |
| MBE growth of epitaxial layers on selected areas of a growth surface (e.g., wafer or epi-layer grown thereon) is achieved by masking portions of the surface with an amorphous material and directing molecular beams at the masked surface so that a polycrystalline layer deposits on the mask |
| 4099305 |
Fabrication of mesa devices by MBE growth over channeled substrates |
July 11, 1978 |
| Parallel channels are separated by ridges formed in a semiconductor body in such a way that each channel is wider at its base than at its top. Molecular beam epitaxy is used to deposit semiconductor layers on the ridges and in the channels. Because each channel is narrower at its top |
| 4001858 |
Simultaneous molecular beam deposition of monocrystalline and polycrystalline III(a)-V(a) compou |
January 4, 1977 |
| Described is a molecular beam technique for fabricating semiconductor devices from Group III(a)-V(a) compounds. To form planar isolated devices, an amorphous insulative layer is formed on selected portions of a monocrystalline substrate of the Group III(a)-V(a) material which is at l |
| 3974002 |
MBE growth: gettering contaminants and fabricating heterostructure junction lasers |
August 10, 1976 |
| In the fabrication of double heterostructure GaAsAlGaAs junction lasers by molecular beam epitaxy, it has been found that suitably annealing the entire heterostructure increases the external quantum efficiency of the laser and reduces the room temperature threshold for lasing. Also d |
| 3969164 |
Native oxide technique for preparing clean substrate surfaces |
July 13, 1976 |
| Surface contamination of Group III(a)-V(a) substrates prior to epitaxial growth can influence structural, optical, and electrical properties of the resulting layers. Of the common contaminants, sulfur, nitrogen, carbon, and oxygen, which are found on substrate surfaces, only carbon canno |
| 3941624 |
Sn-Doped group III(a)-v(a) Ga-containing layers grown by molecular beam epitaxy |
March 2, 1976 |
| In order to insure that the doping profiles of Sn-doped Group III(a)-V(a) Ga-containing layers grown by molecular beam epitaxy follow relatively closely the time-intensity profile of the dopant beam, the substrate temperature should not exceed about 550.degree.C. |
