Abstract: The present invention is directed to an ultra-compact dual quantum cascade laser assembly that nearly doubles the strength of a traditional laser in a in a single hermetically sealed micropackage. The device may comprise two quantum cascade lasers that meet at a combiner to create a single laser with a higher strength than traditional lasers. The current invention provides a path to an ultra-compact coherent beam combing arrangement that uses both dichroic beam combining and polarization beam combining techniques.

Abstract: A semiconductor laser tuned with an acousto-optic modulator. The acousto-optic modulator may generate standing waves or traveling waves. When traveling waves are used, a second acousto-optic modulator may be used in a reverse orientation to cancel out a chirp created in the first acousto-optic modulator. The acousto-optic modulator may be used with standing-wave laser resonators or ring lasers.

Abstract: The present invention is directed to an ultra-compact dual quantum cascade laser assembly that nearly doubles the strength of a traditional laser in a in a single hermetically sealed micropackage. The device may comprise two quantum cascade lasers that meet at a combiner to create a single laser with a higher strength than traditional lasers. The current invention provides a path to an ultra-compact coherent beam combing arrangement that uses both dichroic beam combining and polarization beam combining techniques.

Abstract: A semiconductor laser tuned with an acousto-optic modulator. The acousto-optic modulator may generate standing waves or traveling waves. When traveling waves are used, a second acousto-optic modulator may be used in a reverse orientation to cancel out a chirp created in the first acousto-optic modulator. The acousto-optic modulator may be used with standing-wave laser resonators or ring lasers.

Abstract: The present invention is directed to an ultra-compact dual quantum cascade laser assembly that nearly doubles the strength of a traditional laser in a in a single hermetically sealed micropackage. The device may comprise two quantum cascade lasers that meet at a combiner to create a single laser with a higher strength than traditional lasers. The current invention provides a path to an ultra-compact coherent beam combing arrangement that uses both dichroic beam combining and polarization beam combining techniques.

Abstract: A semiconductor laser tuned with an acousto-optic modulator. The acousto-optic modulator may generate standing waves or traveling waves. When traveling waves are used, a second acousto-optic modulator may be used in a reverse orientation to cancel out a chirp created in the first acousto-optic modulator. The acousto-optic modulator may be used with standing-wave laser resonators or ring lasers.

Abstract: A semiconductor laser tuned with an acousto-optic modulator. The acousto-optic modulator may generate standing waves or traveling waves. When traveling waves are used, a second acousto-optic modulator may be used in a reverse orientation to cancel out a chirp created in the first acousto-optic modulator. The acousto-optic modulator may be used with standing-wave laser resonators or ring lasers.

Abstract: The present invention is directed to an ultra-compact dual quantum cascade laser assembly that nearly doubles the strength of a traditional laser in a in a single hermetically sealed micropackage. The device may comprise two quantum cascade lasers that meet at a combiner to create a single laser with a higher strength than traditional lasers. The current invention provides a path to an ultra-compact coherent beam combing arrangement that uses both dichroic beam combining and polarization beam combining techniques.

Abstract: The present invention is directed to an ultra-compact dual quantum cascade laser assembly that nearly doubles the strength of a traditional laser in a in a single hermetically sealed micropackage. The device may comprise two quantum cascade lasers that meet at a combiner to create a single laser with a higher strength than traditional lasers. The current invention provides a path to an ultra-compact coherent beam combing arrangement that uses both dichroic beam combining and polarization beam combining techniques.

Abstract: A semiconductor laser tuned with an acousto-optic modulator. The acousto-optic modulator may generate standing waves or traveling waves. When traveling waves are used, a second acousto-optic modulator may be used in a reverse orientation to cancel out a chirp created in the first acousto-optic modulator. The acousto-optic modulator may be used with standing-wave laser resonators or ring lasers.

Abstract: The present invention is directed to an ultra-compact dual quantum cascade laser assembly that nearly doubles the strength of a traditional laser in a in a single hermetically sealed micropackage. The device may comprise two quantum cascade lasers that meet at a combiner to create a single laser with a higher strength than traditional lasers. The current invention provides a path to an ultra-compact coherent beam combing arrangement that uses both dichroic beam combining and polarization beam combining techniques.

Abstract: A semiconductor laser tuned with an acousto-optic modulator. The acousto-optic modulator may generate standing waves or traveling waves. When traveling waves are used, a second acousto-optic modulator may be used in a reverse orientation to cancel out a chirp created in the first acousto-optic modulator. The acousto-optic modulator may be used with standing-wave laser resonators or ring lasers.

Abstract: A semiconductor laser tuned with an acousto-optic modulator. The acousto-optic modulator may generate standing waves or traveling waves. When traveling waves are used, a second acousto-optic modulator may be used in a reverse orientation to cancel out a chirp created in the first acousto-optic modulator. The acousto-optic modulator may be used with standing-wave laser resonators or ring lasers.

Abstract: A semiconductor laser tuned with an acousto-optic modulator. The acousto-optic modulator may generate standing waves or traveling waves. When traveling waves are used, a second acousto-optic modulator may be used in a reverse orientation to cancel out a chirp created in the first acousto-optic modulator. The acousto-optic modulator may be used with standing-wave laser resonators or ring lasers.

Abstract: An improved longwave infrared quantum cascade laser. The improvement includes a strained InxGa1-xAs/AlyIn1-yAs composition, with x and y each between 0.53 and 1, an active region emitting at a wavelength equal to or greater than 8 ?m, an energy spacing E54 equal to or greater than 50 meV, an energy spacing EC4 equal to or greater than 250 meV, and an optical waveguide with a cladding layer on each side of the active region. Each cladding layer has a doping level of about 2·1016 cm?3. The optical waveguide also has a top InP layer with a doping level of about 5·1016 cm?3 and a bottom InP layer with a doping level of about 5?1016 cm?3. Additionally, the optical waveguide has a plasmon layer with a doping level of about 8·1018 cm?3.

Abstract: An improved longwave infrared quantum cascade laser. The improvement includes a strained composition, with x and y each between 0.53 and 1, an active region emitting at a wavelength equal to or greater than 8 ?m, an energy spacing E54 equal to or greater than 50 meV, an energy spacing EC4 equal to or greater than 250 meV, and an optical waveguide with a cladding layer on each side of the active region. Each cladding layer has a doping level of about 2·1016 cm?3. The optical waveguide also has a top InP layer with a doping level of about 5·1016 cm?3 and a bottom InP layer with a doping level of about 5?1016 cm?3. Additionally, the optical waveguide has a plasmon layer with a doping level of about 8·1018 cm?3.

Abstract: An improved quantum cascade laser, the improvement comprising a longitudinally non-uniform dielectric waveguide. The waveguide includes a longitudinally straight section and a longitudinally tapered section. The length of the tapered section is between 5% and 50% of the total cavity length. The tapered section tapers at a taper angle from the facet width to the ridge width. The taper angle is smaller than the delineation angle of the waveguide.

Abstract: A method for detecting component concentrations in human gas emissions such as breath and gas emitted from skin. A gas sample containing a specified component is collected into a gas cell using a pump and a series of valves to draw the gas sample into the cell and control the gas pressure within the cell. A tunable optical radiation beam is passed through the gas cell and the amount of energy absorbed by the specified component may be measured indirectly by taking the difference between the incident and emerging beam energy or directly by optoacoustic methods. Concentrations of the specified component as small as 0.1 ppB may be determined. Additionally, the tunable optical radiation beam may be multiplexed for use with a plurality of systems utilizing the beam for medical purposes.

Abstract: A method for detecting component concentrations in human gas emissions such as breath and gas emitted from skin. A gas sample containing a specified component is collected into a gas cell using a pump and a series of valves to draw the gas sample into the cell and control the gas pressure within the cell. A tunable optical radiation beam is passed through the gas cell and the amount of energy absorbed by the specified component may be measured indirectly by taking the difference between the incident and emerging beam energy or directly by optoacoustic methods. Concentrations of the specified component as small as 0.1 ppB may be determined. Additionally, the tunable optical radiation beam may be multiplexed for use with a plurality of systems utilizing the beam for medical purposes.

Abstract: A quantum cascade laser having a lower laser level backfilling given by an equation that accounts for the degeneracy of energy states due to the presence of multiple subbands. For mid-infrared quantum cascade lasers at room temperature and a typical number of injector subbands, the voltage defect is between 90 meV and 110 meV at a current density of 80% of the rollover current density.