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David A. Ritchie - One of the best experts on this subject based on the ideXlab platform.
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high resolution Gas phase spectroscopy with a distributed feedback terahertz quantum cascade Laser
Applied Physics Letters, 2006Co-Authors: Heinz-wilhelm Hübers, Alexey Semenov, Lukas Mahler, Alessandro Tredicucci, Harvey E. Beere, Heiko Richter, S G Pavlov, David A. RitchieAbstract:The quantum cascade Laser is a powerful, narrow linewidth, and continuous wave source of terahertz radiation. The authors have implemented a distributed feedback device in a spectrometer for high-resolution Gas phase spectroscopy. Amplitude as well as frequency modulation schemes have been realized. The absolute frequency was determined by mixing the radiation from the quantum cascade Laser with that from a Gas Laser. The pressure broadening and the pressure shift of a rotational transition of methanol at 2.519THz were measured in order to demonstrate the performance of the spectrometer.The quantum cascade Laser is a powerful, narrow linewidth, and continuous wave source of terahertz radiation. The authors have implemented a distributed feedback device in a spectrometer for high-resolution Gas phase spectroscopy. Amplitude as well as frequency modulation schemes have been realized. The absolute frequency was determined by mixing the radiation from the quantum cascade Laser with that from a Gas Laser. The pressure broadening and the pressure shift of a rotational transition of methanol at 2.519THz were measured in order to demonstrate the performance of the spectrometer.
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high resolution Gas phase spectroscopy with a distributed feedback terahertz quantum cascade Laser
Applied Physics Letters, 2006Co-Authors: Heinz-wilhelm Hübers, Alexey Semenov, Lukas Mahler, Alessandro Tredicucci, Harvey E. Beere, Heiko Richter, S G Pavlov, David A. RitchieAbstract:The quantum cascade Laser is a powerful, narrow linewidth, and continuous wave source of terahertz radiation. The authors have implemented a distributed feedback device in a spectrometer for high-resolution Gas phase spectroscopy. Amplitude as well as frequency modulation schemes have been realized. The absolute frequency was determined by mixing the radiation from the quantum cascade Laser with that from a Gas Laser. The pressure broadening and the pressure shift of a rotational transition of methanol at 2.519THz were measured in order to demonstrate the performance of the spectrometer.
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heterodyne receiver at 2 5 thz with quantum cascade Laser and hot electron bolometric mixer
Proceedings of SPIE, 2006Co-Authors: Heinz-wilhelm Hübers, Alexey Semenov, Lukas Mahler, Alessandro Tredicucci, Harvey E. Beere, Heiko Richter, S G Pavlov, David A. RitchieAbstract:Quantum cascade Lasers (QCLs) operating at 2.5 THz have been used for Gas phase spectroscopy and as local oscillator in a heterodyne receiver. One QCL has a Fabry-Perot resonator while the other has a distributed feedback resonator. The linewidth and frequency tunability of both QCLs have been investigated by either mixing two modes of the QCL or by mixing the emission from the QCL with the emission from a 2.5 THz Gas Laser. The frequency tunability as well as the linewidth is sufficient for Doppler limited spectroscopy of methanol Gas. The QCLs have been used successfully as local oscillators in a heterodyne receiver. Noise temperature measurements with a hot electron bolometer and a QCL yielded the same result as with a Gas Laser as local oscillator.
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Terahertz quantum cascade Laser as local oscillator in a heterodyne receiver
Optics Express, 2005Co-Authors: Heinz-wilhelm Hübers, Sergey Pavlov, Alexey Semenov, R. Kohler, Lukas Mahler, Alessandro Tredicucci, Harvey E. Beere, David A. Ritchie, Edmund H. LinfieldAbstract:Terahertz quantum cascade Lasers have been investigated with respect to their performance as a local oscillator in a heterodyne receiver. The beam profile has been measured and transformed in to a close to Gaussian profile resulting in a good matching between the field patterns of the quantum cascade Laser and the antenna of a superconducting hot electron bolometric mixer. Noise temperature measurements with the hot electron bolometer and a 2.5 THz quantum cascade Laser yielded the same result as with a Gas Laser as local oscillator.
F Benabid - One of the best experts on this subject based on the ideXlab platform.
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near diffraction limited performance of an opa pumped acetylene filled hollow core fiber Laser in the mid ir
Optics Express, 2017Co-Authors: Neda Dadashzadeh, F Benabid, Manasadevi P Thirugnanasambandam, H Kushan W Weerasinghe, Benoit Debord, Matthieu Chafer, Frederic Gerome, Brian R Washburn, Kristan L CorwinAbstract:We investigate the mid-IR Laser beam characteristics from an acetylene-filled hollow-core optical fiber Gas Laser (HOFGLAS) system. The Laser exhibits near-diffraction limited beam quality in the 3 μm region with M2 = 1.15 ± 0.02 measured at high pulse energy, and the highest mid-IR pulse energy from a HOFGLAS system of 1.4 μJ is reported. Furthermore, the effects of output saturation with pump pulse energy are reduced through the use of longer fibers with low loss. Finally, the slope efficiency is shown to be nearly independent of Gas pressure over a wide range, which is encouraging for further output power increase.
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hollow core optical fiber Gas Lasers hofglas a review invited
Optical Materials Express, 2012Co-Authors: A Vasudevan V Nampoothiri, Andrew M Jones, Coralie Fourcade Dutin, Neda Dadashzadeh, Bastian Baumgart, Yingying Wang, M Alharbi, T D Bradley, N Campbell, F BenabidAbstract:The development of hollow core photonic crystal fibers with low losses over a broad spectral region in the near IR enabled the demonstration of a novel Laser type - Hollow-core Optical Fiber Gas Laser (HOFGLAS). The Laser combines attractive features of fiber Lasers such as compactness and long interaction length of pump and Laser radiation with those of Gas Lasers such as the potential for high output power and narrow line width. This paper summarizes recent developments and describes the demonstration of C2H2 and HCN prototype Lasers. Avenues to extend Laser emission further into the IR are discussed.
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mid infrared Gas filled photonic crystal fiber Laser based on population inversion
Optics Express, 2011Co-Authors: Andrew M Jones, A Vasudevan V Nampoothiri, F Benabid, Brian R Washburn, Amarin Ratanavis, Tobias Fiedler, N V Wheeler, F Couny, Rajesh Kadel, Kristan L CorwinAbstract:We demonstrate for the first time an optically pumped Gas Laser based on population inversion using a hollow core photonic crystal fiber (HC-PCF). The HC-PCF filled with 12C2H2 Gas is pumped with ~5 ns pulses at 1.52 μm and lases at 3.12 μm and 3.16 μm in the mid-infrared spectral region. The maximum measured Laser pulse energy of ~6 nJ was obtained at a Gas pressure of 7 torr with a fiber with 20 dB/m loss near the lasing wavelengths. While the measured slope efficiencies of this prototype did not exceed a few percent due mainly to linear losses of the fiber at the Laser wavelengths, 25% slope efficiency and pulse energies of a few mJ are the predicted limits of this Laser. Simulations of the Laser's behavior agree qualitatively with experimental observations.
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subwatt threshold cw raman fiber Gas Laser based on h 2 filled hollow core photonic crystal fiber
Physical Review Letters, 2007Co-Authors: F Couny, F Benabid, P S LightAbstract:We report on what is, to our knowledge, the first cw pumped Raman fiber-Gas Laser based on a hollow-core photonic crystal fiber filled with hydrogen. The high efficiency of the Gas-Laser interaction inside the fiber allows operation in a single-pass configuration. The transmitted spectrum exhibits 99.99% of the output light at the Stokes wavelength and a pump power threshold as low as 2.25 W. The study of the Stokes emission evolution with pressure shows that highly efficient Raman amplification is still possible even at atmospheric pressure. The addition of fiber Bragg gratings to the system, creating a cavity at the Stokes wavelength, reduces the Raman threshold power below 600 mW.
Heinz-wilhelm Hübers - One of the best experts on this subject based on the ideXlab platform.
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high resolution Gas phase spectroscopy with a distributed feedback terahertz quantum cascade Laser
Applied Physics Letters, 2006Co-Authors: Heinz-wilhelm Hübers, Alexey Semenov, Lukas Mahler, Alessandro Tredicucci, Harvey E. Beere, Heiko Richter, S G Pavlov, David A. RitchieAbstract:The quantum cascade Laser is a powerful, narrow linewidth, and continuous wave source of terahertz radiation. The authors have implemented a distributed feedback device in a spectrometer for high-resolution Gas phase spectroscopy. Amplitude as well as frequency modulation schemes have been realized. The absolute frequency was determined by mixing the radiation from the quantum cascade Laser with that from a Gas Laser. The pressure broadening and the pressure shift of a rotational transition of methanol at 2.519THz were measured in order to demonstrate the performance of the spectrometer.The quantum cascade Laser is a powerful, narrow linewidth, and continuous wave source of terahertz radiation. The authors have implemented a distributed feedback device in a spectrometer for high-resolution Gas phase spectroscopy. Amplitude as well as frequency modulation schemes have been realized. The absolute frequency was determined by mixing the radiation from the quantum cascade Laser with that from a Gas Laser. The pressure broadening and the pressure shift of a rotational transition of methanol at 2.519THz were measured in order to demonstrate the performance of the spectrometer.
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high resolution Gas phase spectroscopy with a distributed feedback terahertz quantum cascade Laser
Applied Physics Letters, 2006Co-Authors: Heinz-wilhelm Hübers, Alexey Semenov, Lukas Mahler, Alessandro Tredicucci, Harvey E. Beere, Heiko Richter, S G Pavlov, David A. RitchieAbstract:The quantum cascade Laser is a powerful, narrow linewidth, and continuous wave source of terahertz radiation. The authors have implemented a distributed feedback device in a spectrometer for high-resolution Gas phase spectroscopy. Amplitude as well as frequency modulation schemes have been realized. The absolute frequency was determined by mixing the radiation from the quantum cascade Laser with that from a Gas Laser. The pressure broadening and the pressure shift of a rotational transition of methanol at 2.519THz were measured in order to demonstrate the performance of the spectrometer.
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heterodyne receiver at 2 5 thz with quantum cascade Laser and hot electron bolometric mixer
Proceedings of SPIE, 2006Co-Authors: Heinz-wilhelm Hübers, Alexey Semenov, Lukas Mahler, Alessandro Tredicucci, Harvey E. Beere, Heiko Richter, S G Pavlov, David A. RitchieAbstract:Quantum cascade Lasers (QCLs) operating at 2.5 THz have been used for Gas phase spectroscopy and as local oscillator in a heterodyne receiver. One QCL has a Fabry-Perot resonator while the other has a distributed feedback resonator. The linewidth and frequency tunability of both QCLs have been investigated by either mixing two modes of the QCL or by mixing the emission from the QCL with the emission from a 2.5 THz Gas Laser. The frequency tunability as well as the linewidth is sufficient for Doppler limited spectroscopy of methanol Gas. The QCLs have been used successfully as local oscillators in a heterodyne receiver. Noise temperature measurements with a hot electron bolometer and a QCL yielded the same result as with a Gas Laser as local oscillator.
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Terahertz quantum cascade Laser as local oscillator in a heterodyne receiver
Optics Express, 2005Co-Authors: Heinz-wilhelm Hübers, Sergey Pavlov, Alexey Semenov, R. Kohler, Lukas Mahler, Alessandro Tredicucci, Harvey E. Beere, David A. Ritchie, Edmund H. LinfieldAbstract:Terahertz quantum cascade Lasers have been investigated with respect to their performance as a local oscillator in a heterodyne receiver. The beam profile has been measured and transformed in to a close to Gaussian profile resulting in a good matching between the field patterns of the quantum cascade Laser and the antenna of a superconducting hot electron bolometric mixer. Noise temperature measurements with the hot electron bolometer and a 2.5 THz quantum cascade Laser yielded the same result as with a Gas Laser as local oscillator.
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heterodyne receiver for 3 5 thz with hot electron bolometer mixer
Proceedings of SPIE, 2004Co-Authors: Heinz-wilhelm Hübers, Heiko Richter, Alexei Semenov, G N Goltsman, Martin Schwarz, Burghardt Gunther, K Smirnov, B VoronovAbstract:Heterodyne receivers for applications in astronomy and planetary research need quantum limited sensitivity. In instruments which are currently build for SOFIA and Herschel superconducting hot electron bolometers (HEB) will be used to achieve this goal at frequencies above 1.4 THz. The local oscillator and the mixer are the most critical components for a heterodyne receiver operating at 3-5 THz. The design and performance of an optically pumped THz Gas Laser optimized for this frequency band will be presented. In order to optimize the performance for this frequency hot electron bolometer mixers with different in-plane dimensions and logarithmic-spiral feed antennas have been investigated. Their noise temperatures and beam patterns were measured. Above 3 THz the best performance was achieved with a superconducting bridge of 2.0 x 0.2 μm2 incorporated in a logarithmic spiral antenna. The DSB noise temperatures were 2700 K, 4700 K and 6400 K at 3.1 THz, 4.3 THz and 5.2 THz, respectively. The results demonstrate that the NbN HEB is very well suited as a mixer for THz heterodyne receivers up to at least 5 THz.
Kristan L Corwin - One of the best experts on this subject based on the ideXlab platform.
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near diffraction limited performance of an opa pumped acetylene filled hollow core fiber Laser in the mid ir
Optics Express, 2017Co-Authors: Neda Dadashzadeh, F Benabid, Manasadevi P Thirugnanasambandam, H Kushan W Weerasinghe, Benoit Debord, Matthieu Chafer, Frederic Gerome, Brian R Washburn, Kristan L CorwinAbstract:We investigate the mid-IR Laser beam characteristics from an acetylene-filled hollow-core optical fiber Gas Laser (HOFGLAS) system. The Laser exhibits near-diffraction limited beam quality in the 3 μm region with M2 = 1.15 ± 0.02 measured at high pulse energy, and the highest mid-IR pulse energy from a HOFGLAS system of 1.4 μJ is reported. Furthermore, the effects of output saturation with pump pulse energy are reduced through the use of longer fibers with low loss. Finally, the slope efficiency is shown to be nearly independent of Gas pressure over a wide range, which is encouraging for further output power increase.
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mid infrared Gas filled photonic crystal fiber Laser based on population inversion
Optics Express, 2011Co-Authors: Andrew M Jones, A Vasudevan V Nampoothiri, F Benabid, Brian R Washburn, Amarin Ratanavis, Tobias Fiedler, N V Wheeler, F Couny, Rajesh Kadel, Kristan L CorwinAbstract:We demonstrate for the first time an optically pumped Gas Laser based on population inversion using a hollow core photonic crystal fiber (HC-PCF). The HC-PCF filled with 12C2H2 Gas is pumped with ~5 ns pulses at 1.52 μm and lases at 3.12 μm and 3.16 μm in the mid-infrared spectral region. The maximum measured Laser pulse energy of ~6 nJ was obtained at a Gas pressure of 7 torr with a fiber with 20 dB/m loss near the lasing wavelengths. While the measured slope efficiencies of this prototype did not exceed a few percent due mainly to linear losses of the fiber at the Laser wavelengths, 25% slope efficiency and pulse energies of a few mJ are the predicted limits of this Laser. Simulations of the Laser's behavior agree qualitatively with experimental observations.
Lukas Mahler - One of the best experts on this subject based on the ideXlab platform.
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high resolution Gas phase spectroscopy with a distributed feedback terahertz quantum cascade Laser
Applied Physics Letters, 2006Co-Authors: Heinz-wilhelm Hübers, Alexey Semenov, Lukas Mahler, Alessandro Tredicucci, Harvey E. Beere, Heiko Richter, S G Pavlov, David A. RitchieAbstract:The quantum cascade Laser is a powerful, narrow linewidth, and continuous wave source of terahertz radiation. The authors have implemented a distributed feedback device in a spectrometer for high-resolution Gas phase spectroscopy. Amplitude as well as frequency modulation schemes have been realized. The absolute frequency was determined by mixing the radiation from the quantum cascade Laser with that from a Gas Laser. The pressure broadening and the pressure shift of a rotational transition of methanol at 2.519THz were measured in order to demonstrate the performance of the spectrometer.The quantum cascade Laser is a powerful, narrow linewidth, and continuous wave source of terahertz radiation. The authors have implemented a distributed feedback device in a spectrometer for high-resolution Gas phase spectroscopy. Amplitude as well as frequency modulation schemes have been realized. The absolute frequency was determined by mixing the radiation from the quantum cascade Laser with that from a Gas Laser. The pressure broadening and the pressure shift of a rotational transition of methanol at 2.519THz were measured in order to demonstrate the performance of the spectrometer.
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high resolution Gas phase spectroscopy with a distributed feedback terahertz quantum cascade Laser
Applied Physics Letters, 2006Co-Authors: Heinz-wilhelm Hübers, Alexey Semenov, Lukas Mahler, Alessandro Tredicucci, Harvey E. Beere, Heiko Richter, S G Pavlov, David A. RitchieAbstract:The quantum cascade Laser is a powerful, narrow linewidth, and continuous wave source of terahertz radiation. The authors have implemented a distributed feedback device in a spectrometer for high-resolution Gas phase spectroscopy. Amplitude as well as frequency modulation schemes have been realized. The absolute frequency was determined by mixing the radiation from the quantum cascade Laser with that from a Gas Laser. The pressure broadening and the pressure shift of a rotational transition of methanol at 2.519THz were measured in order to demonstrate the performance of the spectrometer.
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heterodyne receiver at 2 5 thz with quantum cascade Laser and hot electron bolometric mixer
Proceedings of SPIE, 2006Co-Authors: Heinz-wilhelm Hübers, Alexey Semenov, Lukas Mahler, Alessandro Tredicucci, Harvey E. Beere, Heiko Richter, S G Pavlov, David A. RitchieAbstract:Quantum cascade Lasers (QCLs) operating at 2.5 THz have been used for Gas phase spectroscopy and as local oscillator in a heterodyne receiver. One QCL has a Fabry-Perot resonator while the other has a distributed feedback resonator. The linewidth and frequency tunability of both QCLs have been investigated by either mixing two modes of the QCL or by mixing the emission from the QCL with the emission from a 2.5 THz Gas Laser. The frequency tunability as well as the linewidth is sufficient for Doppler limited spectroscopy of methanol Gas. The QCLs have been used successfully as local oscillators in a heterodyne receiver. Noise temperature measurements with a hot electron bolometer and a QCL yielded the same result as with a Gas Laser as local oscillator.
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Terahertz quantum cascade Laser as local oscillator in a heterodyne receiver
Optics Express, 2005Co-Authors: Heinz-wilhelm Hübers, Sergey Pavlov, Alexey Semenov, R. Kohler, Lukas Mahler, Alessandro Tredicucci, Harvey E. Beere, David A. Ritchie, Edmund H. LinfieldAbstract:Terahertz quantum cascade Lasers have been investigated with respect to their performance as a local oscillator in a heterodyne receiver. The beam profile has been measured and transformed in to a close to Gaussian profile resulting in a good matching between the field patterns of the quantum cascade Laser and the antenna of a superconducting hot electron bolometric mixer. Noise temperature measurements with the hot electron bolometer and a 2.5 THz quantum cascade Laser yielded the same result as with a Gas Laser as local oscillator.
