Abstract

A tunable quantum-cascade (QC) laser has been flown on NASA’s ER-2 high-altitude aircraft to produce the first atmospheric gas measurements with this newly invented device, an important milestone in the QC laser’s future planetary, industrial, and commercial applications. Using a cryogenically cooled QC laser during a series of 20 aircraft flights beginning in September 1999 and extending through March 2000, we took measurements of methane (CH4) and nitrous oxide (N2O) gas up to ∼20 km in the stratosphere over North America, Scandinavia, and Russia. The QC laser operating near an 8-µm wavelength was produced by the groups of Capasso and Cho of Bell Laboratories, Lucent Technologies, where QC lasers were invented in 1994. Compared with its companion lead salt diode lasers that were also flown on these flights, the single-mode QC laser cooled to 82 K and produced higher output power (10 mW), narrower laser linewidth (17 MHz), increased measurement precision (a factor of 3), and better spectral stability (∼0.1 cm-1 K). The sensitivity of the QC laser channel was estimated to correspond to a minimum-detectable mixing ratio for methane of approximately 2 parts per billion by volume.

© 2001 Optical Society of America

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    [CrossRef]

1999

1998

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

K. Namjou, S. Cai, E. A. Whittaker, J. Faist, C. Gmachl, F. Capasso, D. L. Sivco, A. Y. Cho, “Sensitive absorption spectroscopy with a room-temperature distributed-feedback quantum-cascade laser,” Opt. Lett. 23, 219–221 (1998).
[CrossRef]

S. W. Sharpe, J. F. Kelly, J. S. Hartman, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. Y. Cho, “High-resolution (Doppler-limited) spectroscopy using quantum-cascade distributed-feedback lasers,” Opt. Lett. 23, 1396–1398 (1998).
[CrossRef]

C. Gmachl, F. Capasso, J. Faist, A. L. Hutchinson, A. Tredicucci, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Continuous-wave and high-power pulsed operation of index-coupled distributed feedback quantum cascade laser at λ ≈ 8.5 µm,” Appl. Phys. Lett. 72, 1430–1432 (1998).
[CrossRef]

K. P. Petrov, A. T. Ryan, T. L. Patterson, L. Huang, S. J. Field, “Mid-IR spectroscopic detection of trace gases using guided-wave difference-frequency generation,” Appl. Phys. B 67, 357–361 (1998).
[CrossRef]

1997

C. Gmachl, J. Faist, J. N. Baillargeon, F. Capasso, C. Sirtori, D. L. Sivco, S. N. G. Chu, A. Y. Cho, “Complex-coupled quantum cascade distributed-feedback laser,” IEEE Photon. Technol. Lett. 9, 1090–1092 (1997).
[CrossRef]

1995

M. Tacke, “New developments and applications of tunable IR lead salt lasers,” Infrared Phys. Technol. 36, 447–463 (1995).
[CrossRef]

1994

1993

S. Forouhar, S. Keo, A. Larsson, A. Ksendzov, H. Temkin, “Low-threshold continuous operation of InGaAs/InGaAsP quantum well lasers at 2 microns,” Electron. Lett. 29, 574–576 (1993).
[CrossRef]

1990

Baillargeon, J. N.

C. Gmachl, A. M. Sergent, A. Tredicucci, F. Capasso, A. L. Hutchinson, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Improved cw operation of quantum cascade lasers with epitaxial-side heat-sinking,” IEEE Photon. Technol. Lett. 11, 1369–1371 (1999).
[CrossRef]

R. M. Williams, J. F. Kelly, J. S. Hartman, S. W. Sharpe, M. S. Taubman, J. L. Hall, F. Capasso, C. Gmachl, D. L. Sivco, J. N. Baillargeon, A. Y. Cho, “Kilo-hertz linewidth from frequency stabilized mid-infrared quantum cascade lasers,” Opt. Lett. 24, 1844–1846 (1999).
[CrossRef]

B. A. Paldus, T. G. Spence, R. N. Zare, J. Oomens, F. M. J. Harren, D. H. Parker, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, “Photoacoustic spectroscopy using quantum-cascade lasers,” Opt. Lett. 24, 178–180 (1999).
[CrossRef]

C. Gmachl, F. Capasso, J. Faist, A. L. Hutchinson, A. Tredicucci, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Continuous-wave and high-power pulsed operation of index-coupled distributed feedback quantum cascade laser at λ ≈ 8.5 µm,” Appl. Phys. Lett. 72, 1430–1432 (1998).
[CrossRef]

S. W. Sharpe, J. F. Kelly, J. S. Hartman, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. Y. Cho, “High-resolution (Doppler-limited) spectroscopy using quantum-cascade distributed-feedback lasers,” Opt. Lett. 23, 1396–1398 (1998).
[CrossRef]

C. Gmachl, J. Faist, J. N. Baillargeon, F. Capasso, C. Sirtori, D. L. Sivco, S. N. G. Chu, A. Y. Cho, “Complex-coupled quantum cascade distributed-feedback laser,” IEEE Photon. Technol. Lett. 9, 1090–1092 (1997).
[CrossRef]

Ballard, J.

Beer, R.

Cai, S.

Capasso, F.

R. M. Williams, J. F. Kelly, J. S. Hartman, S. W. Sharpe, M. S. Taubman, J. L. Hall, F. Capasso, C. Gmachl, D. L. Sivco, J. N. Baillargeon, A. Y. Cho, “Kilo-hertz linewidth from frequency stabilized mid-infrared quantum cascade lasers,” Opt. Lett. 24, 1844–1846 (1999).
[CrossRef]

B. A. Paldus, T. G. Spence, R. N. Zare, J. Oomens, F. M. J. Harren, D. H. Parker, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, “Photoacoustic spectroscopy using quantum-cascade lasers,” Opt. Lett. 24, 178–180 (1999).
[CrossRef]

C. Gmachl, A. M. Sergent, A. Tredicucci, F. Capasso, A. L. Hutchinson, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Improved cw operation of quantum cascade lasers with epitaxial-side heat-sinking,” IEEE Photon. Technol. Lett. 11, 1369–1371 (1999).
[CrossRef]

F. Capasso, C. Gmachl, D. L. Sivco, A. Y. Cho, “Quantum cascade lasers,” Phys. World 12, 27–33 (1999).

F. Capasso, C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, A. Y. Cho, “Quantum cascade lasers,” Opt. Photon. News 10(10), 31–37 (1999).

K. Namjou, S. Cai, E. A. Whittaker, J. Faist, C. Gmachl, F. Capasso, D. L. Sivco, A. Y. Cho, “Sensitive absorption spectroscopy with a room-temperature distributed-feedback quantum-cascade laser,” Opt. Lett. 23, 219–221 (1998).
[CrossRef]

C. Gmachl, F. Capasso, J. Faist, A. L. Hutchinson, A. Tredicucci, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Continuous-wave and high-power pulsed operation of index-coupled distributed feedback quantum cascade laser at λ ≈ 8.5 µm,” Appl. Phys. Lett. 72, 1430–1432 (1998).
[CrossRef]

S. W. Sharpe, J. F. Kelly, J. S. Hartman, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. Y. Cho, “High-resolution (Doppler-limited) spectroscopy using quantum-cascade distributed-feedback lasers,” Opt. Lett. 23, 1396–1398 (1998).
[CrossRef]

C. Gmachl, J. Faist, J. N. Baillargeon, F. Capasso, C. Sirtori, D. L. Sivco, S. N. G. Chu, A. Y. Cho, “Complex-coupled quantum cascade distributed-feedback laser,” IEEE Photon. Technol. Lett. 9, 1090–1092 (1997).
[CrossRef]

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, A. Y. Cho, “Quantum cascade laser,” Science 264, 553–555 (1994).
[CrossRef] [PubMed]

Chave, R. G.

Cho, A. Y.

B. A. Paldus, T. G. Spence, R. N. Zare, J. Oomens, F. M. J. Harren, D. H. Parker, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, “Photoacoustic spectroscopy using quantum-cascade lasers,” Opt. Lett. 24, 178–180 (1999).
[CrossRef]

R. M. Williams, J. F. Kelly, J. S. Hartman, S. W. Sharpe, M. S. Taubman, J. L. Hall, F. Capasso, C. Gmachl, D. L. Sivco, J. N. Baillargeon, A. Y. Cho, “Kilo-hertz linewidth from frequency stabilized mid-infrared quantum cascade lasers,” Opt. Lett. 24, 1844–1846 (1999).
[CrossRef]

F. Capasso, C. Gmachl, D. L. Sivco, A. Y. Cho, “Quantum cascade lasers,” Phys. World 12, 27–33 (1999).

F. Capasso, C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, A. Y. Cho, “Quantum cascade lasers,” Opt. Photon. News 10(10), 31–37 (1999).

C. Gmachl, A. M. Sergent, A. Tredicucci, F. Capasso, A. L. Hutchinson, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Improved cw operation of quantum cascade lasers with epitaxial-side heat-sinking,” IEEE Photon. Technol. Lett. 11, 1369–1371 (1999).
[CrossRef]

K. Namjou, S. Cai, E. A. Whittaker, J. Faist, C. Gmachl, F. Capasso, D. L. Sivco, A. Y. Cho, “Sensitive absorption spectroscopy with a room-temperature distributed-feedback quantum-cascade laser,” Opt. Lett. 23, 219–221 (1998).
[CrossRef]

C. Gmachl, F. Capasso, J. Faist, A. L. Hutchinson, A. Tredicucci, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Continuous-wave and high-power pulsed operation of index-coupled distributed feedback quantum cascade laser at λ ≈ 8.5 µm,” Appl. Phys. Lett. 72, 1430–1432 (1998).
[CrossRef]

S. W. Sharpe, J. F. Kelly, J. S. Hartman, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. Y. Cho, “High-resolution (Doppler-limited) spectroscopy using quantum-cascade distributed-feedback lasers,” Opt. Lett. 23, 1396–1398 (1998).
[CrossRef]

C. Gmachl, J. Faist, J. N. Baillargeon, F. Capasso, C. Sirtori, D. L. Sivco, S. N. G. Chu, A. Y. Cho, “Complex-coupled quantum cascade distributed-feedback laser,” IEEE Photon. Technol. Lett. 9, 1090–1092 (1997).
[CrossRef]

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, A. Y. Cho, “Quantum cascade laser,” Science 264, 553–555 (1994).
[CrossRef] [PubMed]

Chu, S. N. G.

C. Gmachl, A. M. Sergent, A. Tredicucci, F. Capasso, A. L. Hutchinson, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Improved cw operation of quantum cascade lasers with epitaxial-side heat-sinking,” IEEE Photon. Technol. Lett. 11, 1369–1371 (1999).
[CrossRef]

C. Gmachl, F. Capasso, J. Faist, A. L. Hutchinson, A. Tredicucci, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Continuous-wave and high-power pulsed operation of index-coupled distributed feedback quantum cascade laser at λ ≈ 8.5 µm,” Appl. Phys. Lett. 72, 1430–1432 (1998).
[CrossRef]

C. Gmachl, J. Faist, J. N. Baillargeon, F. Capasso, C. Sirtori, D. L. Sivco, S. N. G. Chu, A. Y. Cho, “Complex-coupled quantum cascade distributed-feedback laser,” IEEE Photon. Technol. Lett. 9, 1090–1092 (1997).
[CrossRef]

Elkins, J. W.

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

Faist, J.

C. Gmachl, F. Capasso, J. Faist, A. L. Hutchinson, A. Tredicucci, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Continuous-wave and high-power pulsed operation of index-coupled distributed feedback quantum cascade laser at λ ≈ 8.5 µm,” Appl. Phys. Lett. 72, 1430–1432 (1998).
[CrossRef]

K. Namjou, S. Cai, E. A. Whittaker, J. Faist, C. Gmachl, F. Capasso, D. L. Sivco, A. Y. Cho, “Sensitive absorption spectroscopy with a room-temperature distributed-feedback quantum-cascade laser,” Opt. Lett. 23, 219–221 (1998).
[CrossRef]

C. Gmachl, J. Faist, J. N. Baillargeon, F. Capasso, C. Sirtori, D. L. Sivco, S. N. G. Chu, A. Y. Cho, “Complex-coupled quantum cascade distributed-feedback laser,” IEEE Photon. Technol. Lett. 9, 1090–1092 (1997).
[CrossRef]

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, A. Y. Cho, “Quantum cascade laser,” Science 264, 553–555 (1994).
[CrossRef] [PubMed]

Field, S. J.

K. P. Petrov, A. T. Ryan, T. L. Patterson, L. Huang, S. J. Field, “Mid-IR spectroscopic detection of trace gases using guided-wave difference-frequency generation,” Appl. Phys. B 67, 357–361 (1998).
[CrossRef]

Flesch, G. J.

Forouhar, S.

S. Forouhar, S. Keo, A. Larsson, A. Ksendzov, H. Temkin, “Low-threshold continuous operation of InGaAs/InGaAsP quantum well lasers at 2 microns,” Electron. Lett. 29, 574–576 (1993).
[CrossRef]

Gmachl, C.

R. M. Williams, J. F. Kelly, J. S. Hartman, S. W. Sharpe, M. S. Taubman, J. L. Hall, F. Capasso, C. Gmachl, D. L. Sivco, J. N. Baillargeon, A. Y. Cho, “Kilo-hertz linewidth from frequency stabilized mid-infrared quantum cascade lasers,” Opt. Lett. 24, 1844–1846 (1999).
[CrossRef]

B. A. Paldus, T. G. Spence, R. N. Zare, J. Oomens, F. M. J. Harren, D. H. Parker, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, “Photoacoustic spectroscopy using quantum-cascade lasers,” Opt. Lett. 24, 178–180 (1999).
[CrossRef]

C. Gmachl, A. M. Sergent, A. Tredicucci, F. Capasso, A. L. Hutchinson, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Improved cw operation of quantum cascade lasers with epitaxial-side heat-sinking,” IEEE Photon. Technol. Lett. 11, 1369–1371 (1999).
[CrossRef]

F. Capasso, C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, A. Y. Cho, “Quantum cascade lasers,” Opt. Photon. News 10(10), 31–37 (1999).

F. Capasso, C. Gmachl, D. L. Sivco, A. Y. Cho, “Quantum cascade lasers,” Phys. World 12, 27–33 (1999).

K. Namjou, S. Cai, E. A. Whittaker, J. Faist, C. Gmachl, F. Capasso, D. L. Sivco, A. Y. Cho, “Sensitive absorption spectroscopy with a room-temperature distributed-feedback quantum-cascade laser,” Opt. Lett. 23, 219–221 (1998).
[CrossRef]

S. W. Sharpe, J. F. Kelly, J. S. Hartman, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. Y. Cho, “High-resolution (Doppler-limited) spectroscopy using quantum-cascade distributed-feedback lasers,” Opt. Lett. 23, 1396–1398 (1998).
[CrossRef]

C. Gmachl, F. Capasso, J. Faist, A. L. Hutchinson, A. Tredicucci, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Continuous-wave and high-power pulsed operation of index-coupled distributed feedback quantum cascade laser at λ ≈ 8.5 µm,” Appl. Phys. Lett. 72, 1430–1432 (1998).
[CrossRef]

C. Gmachl, J. Faist, J. N. Baillargeon, F. Capasso, C. Sirtori, D. L. Sivco, S. N. G. Chu, A. Y. Cho, “Complex-coupled quantum cascade distributed-feedback laser,” IEEE Photon. Technol. Lett. 9, 1090–1092 (1997).
[CrossRef]

Hall, J. L.

Harren, F. M. J.

Hartman, J. S.

Herman, R. L.

D. C. Scott, R. L. Herman, C. R. Webster, R. D. May, G. J. Flesch, E. J. Moyer, “Airborne Laser Infrared Absorption Spectrometer (ALIAS-II) for in situ atmospheric measurements of N2O, CH4, CO, HCl, and NO2 from balloon or remotely piloted aircraft platforms,” Appl. Opt. 38, 4609–4622 (1999).
[CrossRef]

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

Huang, L.

K. P. Petrov, A. T. Ryan, T. L. Patterson, L. Huang, S. J. Field, “Mid-IR spectroscopic detection of trace gases using guided-wave difference-frequency generation,” Appl. Phys. B 67, 357–361 (1998).
[CrossRef]

Hunten, D. M.

Hutchinson, A. L.

B. A. Paldus, T. G. Spence, R. N. Zare, J. Oomens, F. M. J. Harren, D. H. Parker, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, “Photoacoustic spectroscopy using quantum-cascade lasers,” Opt. Lett. 24, 178–180 (1999).
[CrossRef]

C. Gmachl, A. M. Sergent, A. Tredicucci, F. Capasso, A. L. Hutchinson, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Improved cw operation of quantum cascade lasers with epitaxial-side heat-sinking,” IEEE Photon. Technol. Lett. 11, 1369–1371 (1999).
[CrossRef]

F. Capasso, C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, A. Y. Cho, “Quantum cascade lasers,” Opt. Photon. News 10(10), 31–37 (1999).

C. Gmachl, F. Capasso, J. Faist, A. L. Hutchinson, A. Tredicucci, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Continuous-wave and high-power pulsed operation of index-coupled distributed feedback quantum cascade laser at λ ≈ 8.5 µm,” Appl. Phys. Lett. 72, 1430–1432 (1998).
[CrossRef]

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, A. Y. Cho, “Quantum cascade laser,” Science 264, 553–555 (1994).
[CrossRef] [PubMed]

Kelly, J. F.

Kendall, J.

Keo, S.

S. Forouhar, S. Keo, A. Larsson, A. Ksendzov, H. Temkin, “Low-threshold continuous operation of InGaAs/InGaAsP quantum well lasers at 2 microns,” Electron. Lett. 29, 574–576 (1993).
[CrossRef]

Knollenberg, R. G.

Ksendzov, A.

S. Forouhar, S. Keo, A. Larsson, A. Ksendzov, H. Temkin, “Low-threshold continuous operation of InGaAs/InGaAsP quantum well lasers at 2 microns,” Electron. Lett. 29, 574–576 (1993).
[CrossRef]

Larsson, A.

S. Forouhar, S. Keo, A. Larsson, A. Ksendzov, H. Temkin, “Low-threshold continuous operation of InGaAs/InGaAsP quantum well lasers at 2 microns,” Electron. Lett. 29, 574–576 (1993).
[CrossRef]

Margitan, J. J.

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

May, R. D.

D. C. Scott, R. L. Herman, C. R. Webster, R. D. May, G. J. Flesch, E. J. Moyer, “Airborne Laser Infrared Absorption Spectrometer (ALIAS-II) for in situ atmospheric measurements of N2O, CH4, CO, HCl, and NO2 from balloon or remotely piloted aircraft platforms,” Appl. Opt. 38, 4609–4622 (1999).
[CrossRef]

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

C. R. Webster, R. D. May, C. A. Trimble, R. G. Chave, J. Kendall, “Aircraft (ER-2) laser infrared absorption spectrometer (ALIAS) for in-situ stratospheric measurements of HCl, N2O, CH4, NO2, and HNO3,” Appl. Opt. 33, 454–472 (1994).
[CrossRef] [PubMed]

C. R. Webster, S. P. Sander, R. Beer, R. D. May, R. G. Knollenberg, D. M. Hunten, J. Ballard, “Tunable diode laser infrared spectrometer for in-situ measurements of the gas phase composition and particle size distribution of Titan’s atmosphere,” Appl. Opt. 29, 907–917 (1990).
[CrossRef] [PubMed]

R. D. May, C. R. Webster, “Balloon-borne laser spectrometer measurements of NO2 with gas absorption sensitivities below 10-5,” Appl. Opt. 29, 5042–5044 (1990).
[CrossRef] [PubMed]

C. R. Webster, R. D. May, R. Toumi, J. Pyle, “Active nitrogen partitioning and the nighttime formation of N2O5 in the stratosphere: simultaneous in-situ measurements of NO, NO2, HNO3, O3, N2O, and jNO2 using the BLISS diode laser spectrometer,” J. Geophys. Res. 95, 13851–13866 (1990).
[CrossRef]

Michelsen, H. A.

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

Moyer, E. J.

D. C. Scott, R. L. Herman, C. R. Webster, R. D. May, G. J. Flesch, E. J. Moyer, “Airborne Laser Infrared Absorption Spectrometer (ALIAS-II) for in situ atmospheric measurements of N2O, CH4, CO, HCl, and NO2 from balloon or remotely piloted aircraft platforms,” Appl. Opt. 38, 4609–4622 (1999).
[CrossRef]

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

Namjou, K.

Oomens, J.

Paldus, B. A.

Parker, D. H.

Patterson, T. L.

K. P. Petrov, A. T. Ryan, T. L. Patterson, L. Huang, S. J. Field, “Mid-IR spectroscopic detection of trace gases using guided-wave difference-frequency generation,” Appl. Phys. B 67, 357–361 (1998).
[CrossRef]

Petrov, K. P.

K. P. Petrov, A. T. Ryan, T. L. Patterson, L. Huang, S. J. Field, “Mid-IR spectroscopic detection of trace gases using guided-wave difference-frequency generation,” Appl. Phys. B 67, 357–361 (1998).
[CrossRef]

Pyle, J.

C. R. Webster, R. D. May, R. Toumi, J. Pyle, “Active nitrogen partitioning and the nighttime formation of N2O5 in the stratosphere: simultaneous in-situ measurements of NO, NO2, HNO3, O3, N2O, and jNO2 using the BLISS diode laser spectrometer,” J. Geophys. Res. 95, 13851–13866 (1990).
[CrossRef]

Rosenlof, K. H.

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

Ryan, A. T.

K. P. Petrov, A. T. Ryan, T. L. Patterson, L. Huang, S. J. Field, “Mid-IR spectroscopic detection of trace gases using guided-wave difference-frequency generation,” Appl. Phys. B 67, 357–361 (1998).
[CrossRef]

Salawitch, R. J.

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

Sander, S. P.

Scott, D. C.

D. C. Scott, R. L. Herman, C. R. Webster, R. D. May, G. J. Flesch, E. J. Moyer, “Airborne Laser Infrared Absorption Spectrometer (ALIAS-II) for in situ atmospheric measurements of N2O, CH4, CO, HCl, and NO2 from balloon or remotely piloted aircraft platforms,” Appl. Opt. 38, 4609–4622 (1999).
[CrossRef]

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

Sen, B.

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

Sergent, A. M.

C. Gmachl, A. M. Sergent, A. Tredicucci, F. Capasso, A. L. Hutchinson, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Improved cw operation of quantum cascade lasers with epitaxial-side heat-sinking,” IEEE Photon. Technol. Lett. 11, 1369–1371 (1999).
[CrossRef]

Sharpe, S. W.

Sirtori, C.

C. Gmachl, J. Faist, J. N. Baillargeon, F. Capasso, C. Sirtori, D. L. Sivco, S. N. G. Chu, A. Y. Cho, “Complex-coupled quantum cascade distributed-feedback laser,” IEEE Photon. Technol. Lett. 9, 1090–1092 (1997).
[CrossRef]

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, A. Y. Cho, “Quantum cascade laser,” Science 264, 553–555 (1994).
[CrossRef] [PubMed]

Sivco, D. L.

R. M. Williams, J. F. Kelly, J. S. Hartman, S. W. Sharpe, M. S. Taubman, J. L. Hall, F. Capasso, C. Gmachl, D. L. Sivco, J. N. Baillargeon, A. Y. Cho, “Kilo-hertz linewidth from frequency stabilized mid-infrared quantum cascade lasers,” Opt. Lett. 24, 1844–1846 (1999).
[CrossRef]

B. A. Paldus, T. G. Spence, R. N. Zare, J. Oomens, F. M. J. Harren, D. H. Parker, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. L. Hutchinson, A. Y. Cho, “Photoacoustic spectroscopy using quantum-cascade lasers,” Opt. Lett. 24, 178–180 (1999).
[CrossRef]

C. Gmachl, A. M. Sergent, A. Tredicucci, F. Capasso, A. L. Hutchinson, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Improved cw operation of quantum cascade lasers with epitaxial-side heat-sinking,” IEEE Photon. Technol. Lett. 11, 1369–1371 (1999).
[CrossRef]

F. Capasso, C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, A. Y. Cho, “Quantum cascade lasers,” Opt. Photon. News 10(10), 31–37 (1999).

F. Capasso, C. Gmachl, D. L. Sivco, A. Y. Cho, “Quantum cascade lasers,” Phys. World 12, 27–33 (1999).

K. Namjou, S. Cai, E. A. Whittaker, J. Faist, C. Gmachl, F. Capasso, D. L. Sivco, A. Y. Cho, “Sensitive absorption spectroscopy with a room-temperature distributed-feedback quantum-cascade laser,” Opt. Lett. 23, 219–221 (1998).
[CrossRef]

C. Gmachl, F. Capasso, J. Faist, A. L. Hutchinson, A. Tredicucci, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Continuous-wave and high-power pulsed operation of index-coupled distributed feedback quantum cascade laser at λ ≈ 8.5 µm,” Appl. Phys. Lett. 72, 1430–1432 (1998).
[CrossRef]

S. W. Sharpe, J. F. Kelly, J. S. Hartman, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, A. Y. Cho, “High-resolution (Doppler-limited) spectroscopy using quantum-cascade distributed-feedback lasers,” Opt. Lett. 23, 1396–1398 (1998).
[CrossRef]

C. Gmachl, J. Faist, J. N. Baillargeon, F. Capasso, C. Sirtori, D. L. Sivco, S. N. G. Chu, A. Y. Cho, “Complex-coupled quantum cascade distributed-feedback laser,” IEEE Photon. Technol. Lett. 9, 1090–1092 (1997).
[CrossRef]

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, A. Y. Cho, “Quantum cascade laser,” Science 264, 553–555 (1994).
[CrossRef] [PubMed]

Spence, T. G.

Tacke, M.

M. Tacke, “New developments and applications of tunable IR lead salt lasers,” Infrared Phys. Technol. 36, 447–463 (1995).
[CrossRef]

Taubman, M. S.

Temkin, H.

S. Forouhar, S. Keo, A. Larsson, A. Ksendzov, H. Temkin, “Low-threshold continuous operation of InGaAs/InGaAsP quantum well lasers at 2 microns,” Electron. Lett. 29, 574–576 (1993).
[CrossRef]

Toon, G. C.

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

Toumi, R.

C. R. Webster, R. D. May, R. Toumi, J. Pyle, “Active nitrogen partitioning and the nighttime formation of N2O5 in the stratosphere: simultaneous in-situ measurements of NO, NO2, HNO3, O3, N2O, and jNO2 using the BLISS diode laser spectrometer,” J. Geophys. Res. 95, 13851–13866 (1990).
[CrossRef]

Tredicucci, A.

F. Capasso, C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, A. Y. Cho, “Quantum cascade lasers,” Opt. Photon. News 10(10), 31–37 (1999).

C. Gmachl, A. M. Sergent, A. Tredicucci, F. Capasso, A. L. Hutchinson, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Improved cw operation of quantum cascade lasers with epitaxial-side heat-sinking,” IEEE Photon. Technol. Lett. 11, 1369–1371 (1999).
[CrossRef]

C. Gmachl, F. Capasso, J. Faist, A. L. Hutchinson, A. Tredicucci, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Continuous-wave and high-power pulsed operation of index-coupled distributed feedback quantum cascade laser at λ ≈ 8.5 µm,” Appl. Phys. Lett. 72, 1430–1432 (1998).
[CrossRef]

Trimble, C. A.

Webster, C. R.

D. C. Scott, R. L. Herman, C. R. Webster, R. D. May, G. J. Flesch, E. J. Moyer, “Airborne Laser Infrared Absorption Spectrometer (ALIAS-II) for in situ atmospheric measurements of N2O, CH4, CO, HCl, and NO2 from balloon or remotely piloted aircraft platforms,” Appl. Opt. 38, 4609–4622 (1999).
[CrossRef]

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

C. R. Webster, R. D. May, C. A. Trimble, R. G. Chave, J. Kendall, “Aircraft (ER-2) laser infrared absorption spectrometer (ALIAS) for in-situ stratospheric measurements of HCl, N2O, CH4, NO2, and HNO3,” Appl. Opt. 33, 454–472 (1994).
[CrossRef] [PubMed]

C. R. Webster, S. P. Sander, R. Beer, R. D. May, R. G. Knollenberg, D. M. Hunten, J. Ballard, “Tunable diode laser infrared spectrometer for in-situ measurements of the gas phase composition and particle size distribution of Titan’s atmosphere,” Appl. Opt. 29, 907–917 (1990).
[CrossRef] [PubMed]

R. D. May, C. R. Webster, “Balloon-borne laser spectrometer measurements of NO2 with gas absorption sensitivities below 10-5,” Appl. Opt. 29, 5042–5044 (1990).
[CrossRef] [PubMed]

C. R. Webster, R. D. May, R. Toumi, J. Pyle, “Active nitrogen partitioning and the nighttime formation of N2O5 in the stratosphere: simultaneous in-situ measurements of NO, NO2, HNO3, O3, N2O, and jNO2 using the BLISS diode laser spectrometer,” J. Geophys. Res. 95, 13851–13866 (1990).
[CrossRef]

Whittaker, E. A.

Williams, R. M.

Yung, Y. L.

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

Zare, R. N.

Appl. Opt.

Appl. Phys. B

K. P. Petrov, A. T. Ryan, T. L. Patterson, L. Huang, S. J. Field, “Mid-IR spectroscopic detection of trace gases using guided-wave difference-frequency generation,” Appl. Phys. B 67, 357–361 (1998).
[CrossRef]

Appl. Phys. Lett.

C. Gmachl, F. Capasso, J. Faist, A. L. Hutchinson, A. Tredicucci, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Continuous-wave and high-power pulsed operation of index-coupled distributed feedback quantum cascade laser at λ ≈ 8.5 µm,” Appl. Phys. Lett. 72, 1430–1432 (1998).
[CrossRef]

Electron. Lett.

S. Forouhar, S. Keo, A. Larsson, A. Ksendzov, H. Temkin, “Low-threshold continuous operation of InGaAs/InGaAsP quantum well lasers at 2 microns,” Electron. Lett. 29, 574–576 (1993).
[CrossRef]

Geophys. Res. Lett.

R. L. Herman, D. C. Scott, C. R. Webster, R. D. May, E. J. Moyer, R. J. Salawitch, Y. L. Yung, G. C. Toon, B. Sen, J. J. Margitan, K. H. Rosenlof, H. A. Michelsen, J. W. Elkins, “Tropical entrainment timescales inferred from stratospheric N2O and CH4 observations,” Geophys. Res. Lett. 25, 2781–2784 (1998).
[CrossRef]

IEEE Photon. Technol. Lett.

C. Gmachl, A. M. Sergent, A. Tredicucci, F. Capasso, A. L. Hutchinson, D. L. Sivco, J. N. Baillargeon, S. N. G. Chu, A. Y. Cho, “Improved cw operation of quantum cascade lasers with epitaxial-side heat-sinking,” IEEE Photon. Technol. Lett. 11, 1369–1371 (1999).
[CrossRef]

C. Gmachl, J. Faist, J. N. Baillargeon, F. Capasso, C. Sirtori, D. L. Sivco, S. N. G. Chu, A. Y. Cho, “Complex-coupled quantum cascade distributed-feedback laser,” IEEE Photon. Technol. Lett. 9, 1090–1092 (1997).
[CrossRef]

Infrared Phys. Technol.

M. Tacke, “New developments and applications of tunable IR lead salt lasers,” Infrared Phys. Technol. 36, 447–463 (1995).
[CrossRef]

J. Geophys. Res.

C. R. Webster, R. D. May, R. Toumi, J. Pyle, “Active nitrogen partitioning and the nighttime formation of N2O5 in the stratosphere: simultaneous in-situ measurements of NO, NO2, HNO3, O3, N2O, and jNO2 using the BLISS diode laser spectrometer,” J. Geophys. Res. 95, 13851–13866 (1990).
[CrossRef]

Opt. Lett.

Opt. Photon. News

F. Capasso, C. Gmachl, A. Tredicucci, D. L. Sivco, A. L. Hutchinson, A. Y. Cho, “Quantum cascade lasers,” Opt. Photon. News 10(10), 31–37 (1999).

Phys. World

F. Capasso, C. Gmachl, D. L. Sivco, A. Y. Cho, “Quantum cascade lasers,” Phys. World 12, 27–33 (1999).

Science

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, A. Y. Cho, “Quantum cascade laser,” Science 264, 553–555 (1994).
[CrossRef] [PubMed]

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Figures (5)

Fig. 1
Fig. 1

Schematic of the geometry of a QC DFB laser.

Fig. 2
Fig. 2

NASA’s ER-2 high-altitude aircraft takes off from Dryden Flight Research Center (NASA photo courtesy of Tony Landis). The ALIAS is located in the superpod on the right wing. This payload carries numerous other NASA, National Oceanic and Atmospheric Administration, and university experiments.

Fig. 3
Fig. 3

Chip comprising seven QC DFB lasers mounted onto a gold-coated, oxygen-free copper heat sink designed for compatibility with typical lead salt TDL packages. Only two lasers are wire bonded to connections for use (one as an unused spare).

Fig. 4
Fig. 4

QC laser spectral scans of a reference gas cell, a Ge etalon with a free spectral range of 0.015 cm-1, and the actual flight spectrum showing second-harmonic line shapes from CH4 and N2O. Four spectra such as this are recorded in-flight each 1.3 s, produced from absorption in 80 passes of the 1-m-long multipass cell of ALIAS. During flight, the cell is kept at a constant temperature of 280 K. With increasing current, the QC laser scans to a lower wave number (opposite the lead salt TDL’s, but similar to near-IR TDL’s). Over the full range shown, the frequency tuning exhibits a small nonlinearity, the tuning rate increases by ∼10% with an increase in current. The reference gas cell, which is 5 cm long and contains enough pure gas to absorb fully at line center, is used only for line identification and a mode-purity check, and the small interference fringes that can be seen in the upper trace result from an etalon effect with the cell in the beam.

Fig. 5
Fig. 5

(a) Intercomparison between lead salt TDL and QC final flight data for CH4 measurements over California during the cruise and descent portions of the 16 December 1999 flight. For both channels, data points result from the peak-to-peak magnitude of the second-harmonic line in a 1.3-s spectral average, with appropriate correction. For clarity of comparison, the QC values were displaced to lower values by 50 ppbv. The ER-2 aircraft pressure altitude is also plotted. For this flight, outside air temperatures were typically 212 K during cruise, decreasing to 204 K at the tropopause, and increasing to 270 K on descent. (b) Final 1.3-s flight data for CH4 measurements over Sweden and Russia during ascent, dive, climb, and descent for the 11 March 2000 flight. The lower mixing ratios recorded during the latter one third of the flight are characteristic of sampling the Arctic polar vortex into which air from higher altitudes has descended. The ER-2 aircraft pressure altitude is also plotted. For this flight, outside air temperatures were typically 197 K during cruise and climb, increasing to 270 K on descent.

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