Abstract

Spectroscopic detection of gases can be achieved by measuring a few species-specific absorption lines, requiring very accurate wavelength control. Alternatively, it can be achieved by using many wavelengths spread over a wide range; each wavelength need not be optimal spectroscopically, but all collectively form a unique fingerprint for the species of interest. Statistical regression can be used to quantify their concentrations. An experimental evaluation of this concept involved using a 3.1 μm broadly tunable Sb-based mid-IR laser to discriminate and measure mixtures of acetylene and water vapor with absorption spectral overlaps. As many as 30 wavelengths from 3200 to 3280  cm1 were used to measure 5×5 combinations of the two-gas concentration. Statistical analysis of the results validates the concept. Each gas concentration was consistently and reliably measured without any problem of interference from the other. In addition, the method was sufficiently sensitivite to detect unusual discrepancies by use of statistical analysis. Optimization of the system's detection capability and its receiver-operating characteristics is demonstrated. The results suggest that the statistical multiwavelength broadband approach to detection of gas mixture can be a highly effective alternative to species-specific single-line spectroscopy.

© 2006 Optical Society of America

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    [CrossRef]
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    [CrossRef]
  4. D. Weidmann, F. K. Tittel, T. Aellen, M. Beck, D. Hofstetter, J. Faist, and S. Blaser, "Mid-infrared trace-gas sensing with a quasicontinuous-wave Peltier-cooled distributed feedback quantum cascade laser," Appl. Phys. B 79, 907-913 (2004).
    [CrossRef]
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    [CrossRef]
  9. C. R. Swim, "Review of active chem-bio sensing," in Chemical and Biological Sensing V, P. J. Gardner; ed., Proc. SPIE 5416, 178-185 (2004).
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  12. G. Luo, C. Peng, H. Q. Le, S. S. Pei, H. Lee, W.-Y. Hwang, B. Ishang, and J. Zheng. "Broadly wavelength-tunable external cavity mid-infrared quantum cascade lasers," IEEE J. Quantum Electron. 38, 486-494 (2002).
    [CrossRef]
  13. C. Peng, G. P. Luo, and H. Q. Le, "Broadband, continuous, and fine-tune properties of external-cavity thermoelectric-stabilized mid-infrared quantum-cascade lasers," Appl. Opt. 42, 4877-4882 (2003).
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  18. G. Berden, R. Peeters, and G. Meijer, "Cavity ring-down spectroscopy: experimental schemes and applications," Int. Rev. Phys. Chem. 19, 565-607 (2000).
    [CrossRef]
  19. B. Bakowski, I. Corner, G. Hancock, R. Kotchie, R. Peverall, and G. A. D. Ritchie, "Cavity-enhanced absorption spectroscopy with a rapidly swept diode laser," Appl. Phys. B 75, 745-750 (2002).
    [CrossRef]
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2005 (6)

M. G. Allen, D. J. Cook, B. K. Decker, J. M. Hensley, D. I. Rosen, M. L. Silva, D. M. Sonnenfroh, and R. T. Wainner, "In-situ and stand-off sensing using QC/IC laser technology from 3-100 microns," in Quantum Sensing and Nanophotonic Devices II, M. Razeghi and G. J. Brown, eds., Proc. SPIE 5732, 134-139 (2005).
[CrossRef]

R. Kormann, R. Königstedt, U. Parchatka, J. Lelieveld, and H. Fischer, "QUALITAS: a mid-infrared spectrometer for sensitive trace gas measurements based on quantum cascade lasers in cw operation," Rev. Sci. Instrum. 76, 075102 (2005).
[CrossRef]

M. E. Webber, M. Pushkarsky, and C. K. N. Patel, "Optical detection of chemical warfare agents and toxic industrial chemicals: simulation," J. Appl. Phys. 97, 113101 (2005).
[CrossRef]

A. A. Kosterev, Y. A. Bakhirkin, and F. K. Tittel, "Ultrasensitive gas detection by quartz-enhanced photoacoustic spectroscopy in the fundamental molecular absorption bands region," Appl. Phys. B 80, 133-138 (2005).
[CrossRef]

C. J. Hill and R. Q. Yang, "MBE growth optimization of Sb-based interband cascade lasers," J. Crys. Growth 278, 167-172 (2005).
[CrossRef]

R. Q. Yang, C. J. Hill, L. E. Christensen, and C. R. Webster, "Mid-IR type-II interband cascade lasers and their applications," in Semiconductor and Organic Optoelectronic Materials and Devices, C. E. Zah, Y. Luo, and S. Tsuji, eds., Proc. SPIE 5624, 413-422 (2005), and references therein.
[CrossRef]

2004 (3)

Y. He and B. J. Orr, "Rapid measurement of cavity ringdown absorption spectra with a swept-frequency laser," Appl. Phys. B 79, 941-945 (2004).
[CrossRef]

C. R. Swim, "Review of active chem-bio sensing," in Chemical and Biological Sensing V, P. J. Gardner; ed., Proc. SPIE 5416, 178-185 (2004).
[CrossRef]

D. Weidmann, F. K. Tittel, T. Aellen, M. Beck, D. Hofstetter, J. Faist, and S. Blaser, "Mid-infrared trace-gas sensing with a quasicontinuous-wave Peltier-cooled distributed feedback quantum cascade laser," Appl. Phys. B 79, 907-913 (2004).
[CrossRef]

2003 (3)

M. B. Pushkarsky, M. E. Weber, and C. K. N. Patel, "Ultra-sensitive ambient ammonia detection using CO2 laser based photoacoustic spectroscopy," Appl. Phys. B 77, 381-385 (2003).
[CrossRef]

C. Peng, G. P. Luo, and H. Q. Le, "Broadband, continuous, and fine-tune properties of external-cavity thermoelectric-stabilized mid-infrared quantum-cascade lasers," Appl. Opt. 42, 4877-4882 (2003).

C. Peng, H. L. Zhang, and H. Q. Le, "Mid-infrared external-cavity two-segment quantum-cascade laser," Appl. Phys. Lett. 83, 4098-4100 (2003).
[CrossRef]

2002 (3)

G. Luo, C. Peng, H. Q. Le, S. S. Pei, H. Lee, W.-Y. Hwang, B. Ishang, and J. Zheng. "Broadly wavelength-tunable external cavity mid-infrared quantum cascade lasers," IEEE J. Quantum Electron. 38, 486-494 (2002).
[CrossRef]

D. D. Nelson, J. H. Shorter, J. B. McManus, and M. S. Zahniser, "Sub-part-per-billion detection of nitric oxide in air using a thermoelectrically cooled mid-infrared quantum cascade laser spectrometer," Appl. Phys. B 75, 343-350 (2002).
[CrossRef]

B. Bakowski, I. Corner, G. Hancock, R. Kotchie, R. Peverall, and G. A. D. Ritchie, "Cavity-enhanced absorption spectroscopy with a rapidly swept diode laser," Appl. Phys. B 75, 745-750 (2002).
[CrossRef]

2001 (2)

M. W. Sigrist, M. Nägele, and A. Romann, "Infrared laser spectroscopy for trace gas analysis," in 4th Iberioamerican Meeting on Optics and 7th Latin American Meeting on Optics, Lasers, and their Applications, V. L. Brudny, S. A. Ledesma, and M. C. Marconi, eds., Proc. SPIE 4419, 14-17 (2001).
[CrossRef]

G. P. Luo, C. Peng, H. Q. Le, S. S. Pei, W.-Y. Hwang, B. Ishaug, J. Um, J. N. Baillargeon, and C.-H. Lin, "Grating-tuned external-cavity quantum-cascade semiconductor lasers," Appl. Phys. Lett. 78, 2834-2836 (2001).
[CrossRef]

2000 (2)

M. Nagele and M. W. Sigrist, "Mobile laser spectrometer with novel resonant multipass photoacoustic cell for trace-gas sensing," Appl. Phys. B 70, 895-900 (2000).

G. Berden, R. Peeters, and G. Meijer, "Cavity ring-down spectroscopy: experimental schemes and applications," Int. Rev. Phys. Chem. 19, 565-607 (2000).
[CrossRef]

1999 (1)

D. C. Senft, M. J. Fox, C. M. Hamilton, D. A. Richter, N. S. Higdon, and B. T. Kelly, "Performance characterization and ground testing of an airborne CO2 differential absorption lidar system (Phase II)," in Laser Radar Technology and Applications IV, G. W. Kamerman and C. Werner, eds. Proc. SPIE 3707, 165-176 (1999).
[CrossRef]

1998 (1)

1997 (1)

Aellen, T.

D. Weidmann, F. K. Tittel, T. Aellen, M. Beck, D. Hofstetter, J. Faist, and S. Blaser, "Mid-infrared trace-gas sensing with a quasicontinuous-wave Peltier-cooled distributed feedback quantum cascade laser," Appl. Phys. B 79, 907-913 (2004).
[CrossRef]

Allen, M. G.

M. G. Allen, D. J. Cook, B. K. Decker, J. M. Hensley, D. I. Rosen, M. L. Silva, D. M. Sonnenfroh, and R. T. Wainner, "In-situ and stand-off sensing using QC/IC laser technology from 3-100 microns," in Quantum Sensing and Nanophotonic Devices II, M. Razeghi and G. J. Brown, eds., Proc. SPIE 5732, 134-139 (2005).
[CrossRef]

Baillargeon, J. N.

G. P. Luo, C. Peng, H. Q. Le, S. S. Pei, W.-Y. Hwang, B. Ishaug, J. Um, J. N. Baillargeon, and C.-H. Lin, "Grating-tuned external-cavity quantum-cascade semiconductor lasers," Appl. Phys. Lett. 78, 2834-2836 (2001).
[CrossRef]

Bakhirkin, Y. A.

A. A. Kosterev, Y. A. Bakhirkin, and F. K. Tittel, "Ultrasensitive gas detection by quartz-enhanced photoacoustic spectroscopy in the fundamental molecular absorption bands region," Appl. Phys. B 80, 133-138 (2005).
[CrossRef]

Bakowski, B.

B. Bakowski, I. Corner, G. Hancock, R. Kotchie, R. Peverall, and G. A. D. Ritchie, "Cavity-enhanced absorption spectroscopy with a rapidly swept diode laser," Appl. Phys. B 75, 745-750 (2002).
[CrossRef]

Beck, M.

D. Weidmann, F. K. Tittel, T. Aellen, M. Beck, D. Hofstetter, J. Faist, and S. Blaser, "Mid-infrared trace-gas sensing with a quasicontinuous-wave Peltier-cooled distributed feedback quantum cascade laser," Appl. Phys. B 79, 907-913 (2004).
[CrossRef]

Berden, G.

G. Berden, R. Peeters, and G. Meijer, "Cavity ring-down spectroscopy: experimental schemes and applications," Int. Rev. Phys. Chem. 19, 565-607 (2000).
[CrossRef]

Blaser, S.

D. Weidmann, F. K. Tittel, T. Aellen, M. Beck, D. Hofstetter, J. Faist, and S. Blaser, "Mid-infrared trace-gas sensing with a quasicontinuous-wave Peltier-cooled distributed feedback quantum cascade laser," Appl. Phys. B 79, 907-913 (2004).
[CrossRef]

Cai, S.

Capasso, F.

Cho, A. Y.

Christensen, L. E.

R. Q. Yang, C. J. Hill, L. E. Christensen, and C. R. Webster, "Mid-IR type-II interband cascade lasers and their applications," in Semiconductor and Organic Optoelectronic Materials and Devices, C. E. Zah, Y. Luo, and S. Tsuji, eds., Proc. SPIE 5624, 413-422 (2005), and references therein.
[CrossRef]

Cook, D. J.

M. G. Allen, D. J. Cook, B. K. Decker, J. M. Hensley, D. I. Rosen, M. L. Silva, D. M. Sonnenfroh, and R. T. Wainner, "In-situ and stand-off sensing using QC/IC laser technology from 3-100 microns," in Quantum Sensing and Nanophotonic Devices II, M. Razeghi and G. J. Brown, eds., Proc. SPIE 5732, 134-139 (2005).
[CrossRef]

Corner, I.

B. Bakowski, I. Corner, G. Hancock, R. Kotchie, R. Peverall, and G. A. D. Ritchie, "Cavity-enhanced absorption spectroscopy with a rapidly swept diode laser," Appl. Phys. B 75, 745-750 (2002).
[CrossRef]

Decker, B. K.

M. G. Allen, D. J. Cook, B. K. Decker, J. M. Hensley, D. I. Rosen, M. L. Silva, D. M. Sonnenfroh, and R. T. Wainner, "In-situ and stand-off sensing using QC/IC laser technology from 3-100 microns," in Quantum Sensing and Nanophotonic Devices II, M. Razeghi and G. J. Brown, eds., Proc. SPIE 5732, 134-139 (2005).
[CrossRef]

Faist, J.

D. Weidmann, F. K. Tittel, T. Aellen, M. Beck, D. Hofstetter, J. Faist, and S. Blaser, "Mid-infrared trace-gas sensing with a quasicontinuous-wave Peltier-cooled distributed feedback quantum cascade laser," Appl. Phys. B 79, 907-913 (2004).
[CrossRef]

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

Fischer, H.

R. Kormann, R. Königstedt, U. Parchatka, J. Lelieveld, and H. Fischer, "QUALITAS: a mid-infrared spectrometer for sensitive trace gas measurements based on quantum cascade lasers in cw operation," Rev. Sci. Instrum. 76, 075102 (2005).
[CrossRef]

Fox, M. J.

D. C. Senft, M. J. Fox, C. M. Hamilton, D. A. Richter, N. S. Higdon, and B. T. Kelly, "Performance characterization and ground testing of an airborne CO2 differential absorption lidar system (Phase II)," in Laser Radar Technology and Applications IV, G. W. Kamerman and C. Werner, eds. Proc. SPIE 3707, 165-176 (1999).
[CrossRef]

Gmachl, C.

Hamilton, C. M.

D. C. Senft, M. J. Fox, C. M. Hamilton, D. A. Richter, N. S. Higdon, and B. T. Kelly, "Performance characterization and ground testing of an airborne CO2 differential absorption lidar system (Phase II)," in Laser Radar Technology and Applications IV, G. W. Kamerman and C. Werner, eds. Proc. SPIE 3707, 165-176 (1999).
[CrossRef]

Hancock, G.

B. Bakowski, I. Corner, G. Hancock, R. Kotchie, R. Peverall, and G. A. D. Ritchie, "Cavity-enhanced absorption spectroscopy with a rapidly swept diode laser," Appl. Phys. B 75, 745-750 (2002).
[CrossRef]

He, Y.

Y. He and B. J. Orr, "Rapid measurement of cavity ringdown absorption spectra with a swept-frequency laser," Appl. Phys. B 79, 941-945 (2004).
[CrossRef]

Hensley, J. M.

M. G. Allen, D. J. Cook, B. K. Decker, J. M. Hensley, D. I. Rosen, M. L. Silva, D. M. Sonnenfroh, and R. T. Wainner, "In-situ and stand-off sensing using QC/IC laser technology from 3-100 microns," in Quantum Sensing and Nanophotonic Devices II, M. Razeghi and G. J. Brown, eds., Proc. SPIE 5732, 134-139 (2005).
[CrossRef]

Higdon, N. S.

D. C. Senft, M. J. Fox, C. M. Hamilton, D. A. Richter, N. S. Higdon, and B. T. Kelly, "Performance characterization and ground testing of an airborne CO2 differential absorption lidar system (Phase II)," in Laser Radar Technology and Applications IV, G. W. Kamerman and C. Werner, eds. Proc. SPIE 3707, 165-176 (1999).
[CrossRef]

Hill, C. J.

C. J. Hill and R. Q. Yang, "MBE growth optimization of Sb-based interband cascade lasers," J. Crys. Growth 278, 167-172 (2005).
[CrossRef]

R. Q. Yang, C. J. Hill, L. E. Christensen, and C. R. Webster, "Mid-IR type-II interband cascade lasers and their applications," in Semiconductor and Organic Optoelectronic Materials and Devices, C. E. Zah, Y. Luo, and S. Tsuji, eds., Proc. SPIE 5624, 413-422 (2005), and references therein.
[CrossRef]

Hofstetter, D.

D. Weidmann, F. K. Tittel, T. Aellen, M. Beck, D. Hofstetter, J. Faist, and S. Blaser, "Mid-infrared trace-gas sensing with a quasicontinuous-wave Peltier-cooled distributed feedback quantum cascade laser," Appl. Phys. B 79, 907-913 (2004).
[CrossRef]

Hwang, W.-Y.

G. Luo, C. Peng, H. Q. Le, S. S. Pei, H. Lee, W.-Y. Hwang, B. Ishang, and J. Zheng. "Broadly wavelength-tunable external cavity mid-infrared quantum cascade lasers," IEEE J. Quantum Electron. 38, 486-494 (2002).
[CrossRef]

G. P. Luo, C. Peng, H. Q. Le, S. S. Pei, W.-Y. Hwang, B. Ishaug, J. Um, J. N. Baillargeon, and C.-H. Lin, "Grating-tuned external-cavity quantum-cascade semiconductor lasers," Appl. Phys. Lett. 78, 2834-2836 (2001).
[CrossRef]

Ishang, B.

G. Luo, C. Peng, H. Q. Le, S. S. Pei, H. Lee, W.-Y. Hwang, B. Ishang, and J. Zheng. "Broadly wavelength-tunable external cavity mid-infrared quantum cascade lasers," IEEE J. Quantum Electron. 38, 486-494 (2002).
[CrossRef]

Ishaug, B.

G. P. Luo, C. Peng, H. Q. Le, S. S. Pei, W.-Y. Hwang, B. Ishaug, J. Um, J. N. Baillargeon, and C.-H. Lin, "Grating-tuned external-cavity quantum-cascade semiconductor lasers," Appl. Phys. Lett. 78, 2834-2836 (2001).
[CrossRef]

Jolin, L. J.

Kelly, B. T.

D. C. Senft, M. J. Fox, C. M. Hamilton, D. A. Richter, N. S. Higdon, and B. T. Kelly, "Performance characterization and ground testing of an airborne CO2 differential absorption lidar system (Phase II)," in Laser Radar Technology and Applications IV, G. W. Kamerman and C. Werner, eds. Proc. SPIE 3707, 165-176 (1999).
[CrossRef]

Königstedt, R.

R. Kormann, R. Königstedt, U. Parchatka, J. Lelieveld, and H. Fischer, "QUALITAS: a mid-infrared spectrometer for sensitive trace gas measurements based on quantum cascade lasers in cw operation," Rev. Sci. Instrum. 76, 075102 (2005).
[CrossRef]

Kormann, R.

R. Kormann, R. Königstedt, U. Parchatka, J. Lelieveld, and H. Fischer, "QUALITAS: a mid-infrared spectrometer for sensitive trace gas measurements based on quantum cascade lasers in cw operation," Rev. Sci. Instrum. 76, 075102 (2005).
[CrossRef]

Kosterev, A. A.

A. A. Kosterev, Y. A. Bakhirkin, and F. K. Tittel, "Ultrasensitive gas detection by quartz-enhanced photoacoustic spectroscopy in the fundamental molecular absorption bands region," Appl. Phys. B 80, 133-138 (2005).
[CrossRef]

Kotchie, R.

B. Bakowski, I. Corner, G. Hancock, R. Kotchie, R. Peverall, and G. A. D. Ritchie, "Cavity-enhanced absorption spectroscopy with a rapidly swept diode laser," Appl. Phys. B 75, 745-750 (2002).
[CrossRef]

Le, H. Q.

C. Peng, H. L. Zhang, and H. Q. Le, "Mid-infrared external-cavity two-segment quantum-cascade laser," Appl. Phys. Lett. 83, 4098-4100 (2003).
[CrossRef]

C. Peng, G. P. Luo, and H. Q. Le, "Broadband, continuous, and fine-tune properties of external-cavity thermoelectric-stabilized mid-infrared quantum-cascade lasers," Appl. Opt. 42, 4877-4882 (2003).

G. Luo, C. Peng, H. Q. Le, S. S. Pei, H. Lee, W.-Y. Hwang, B. Ishang, and J. Zheng. "Broadly wavelength-tunable external cavity mid-infrared quantum cascade lasers," IEEE J. Quantum Electron. 38, 486-494 (2002).
[CrossRef]

G. P. Luo, C. Peng, H. Q. Le, S. S. Pei, W.-Y. Hwang, B. Ishaug, J. Um, J. N. Baillargeon, and C.-H. Lin, "Grating-tuned external-cavity quantum-cascade semiconductor lasers," Appl. Phys. Lett. 78, 2834-2836 (2001).
[CrossRef]

Lee, H.

G. Luo, C. Peng, H. Q. Le, S. S. Pei, H. Lee, W.-Y. Hwang, B. Ishang, and J. Zheng. "Broadly wavelength-tunable external cavity mid-infrared quantum cascade lasers," IEEE J. Quantum Electron. 38, 486-494 (2002).
[CrossRef]

Lelieveld, J.

R. Kormann, R. Königstedt, U. Parchatka, J. Lelieveld, and H. Fischer, "QUALITAS: a mid-infrared spectrometer for sensitive trace gas measurements based on quantum cascade lasers in cw operation," Rev. Sci. Instrum. 76, 075102 (2005).
[CrossRef]

Lin, C.-H.

G. P. Luo, C. Peng, H. Q. Le, S. S. Pei, W.-Y. Hwang, B. Ishaug, J. Um, J. N. Baillargeon, and C.-H. Lin, "Grating-tuned external-cavity quantum-cascade semiconductor lasers," Appl. Phys. Lett. 78, 2834-2836 (2001).
[CrossRef]

Luo, G.

G. Luo, C. Peng, H. Q. Le, S. S. Pei, H. Lee, W.-Y. Hwang, B. Ishang, and J. Zheng. "Broadly wavelength-tunable external cavity mid-infrared quantum cascade lasers," IEEE J. Quantum Electron. 38, 486-494 (2002).
[CrossRef]

Luo, G. P.

C. Peng, G. P. Luo, and H. Q. Le, "Broadband, continuous, and fine-tune properties of external-cavity thermoelectric-stabilized mid-infrared quantum-cascade lasers," Appl. Opt. 42, 4877-4882 (2003).

G. P. Luo, C. Peng, H. Q. Le, S. S. Pei, W.-Y. Hwang, B. Ishaug, J. Um, J. N. Baillargeon, and C.-H. Lin, "Grating-tuned external-cavity quantum-cascade semiconductor lasers," Appl. Phys. Lett. 78, 2834-2836 (2001).
[CrossRef]

Mamjou, K.

McManus, J. B.

D. D. Nelson, J. H. Shorter, J. B. McManus, and M. S. Zahniser, "Sub-part-per-billion detection of nitric oxide in air using a thermoelectrically cooled mid-infrared quantum cascade laser spectrometer," Appl. Phys. B 75, 343-350 (2002).
[CrossRef]

Meijer, G.

G. Berden, R. Peeters, and G. Meijer, "Cavity ring-down spectroscopy: experimental schemes and applications," Int. Rev. Phys. Chem. 19, 565-607 (2000).
[CrossRef]

Nagele, M.

M. Nagele and M. W. Sigrist, "Mobile laser spectrometer with novel resonant multipass photoacoustic cell for trace-gas sensing," Appl. Phys. B 70, 895-900 (2000).

Nägele, M.

M. W. Sigrist, M. Nägele, and A. Romann, "Infrared laser spectroscopy for trace gas analysis," in 4th Iberioamerican Meeting on Optics and 7th Latin American Meeting on Optics, Lasers, and their Applications, V. L. Brudny, S. A. Ledesma, and M. C. Marconi, eds., Proc. SPIE 4419, 14-17 (2001).
[CrossRef]

Nelson, D. D.

D. D. Nelson, J. H. Shorter, J. B. McManus, and M. S. Zahniser, "Sub-part-per-billion detection of nitric oxide in air using a thermoelectrically cooled mid-infrared quantum cascade laser spectrometer," Appl. Phys. B 75, 343-350 (2002).
[CrossRef]

Orr, B. J.

Y. He and B. J. Orr, "Rapid measurement of cavity ringdown absorption spectra with a swept-frequency laser," Appl. Phys. B 79, 941-945 (2004).
[CrossRef]

Parchatka, U.

R. Kormann, R. Königstedt, U. Parchatka, J. Lelieveld, and H. Fischer, "QUALITAS: a mid-infrared spectrometer for sensitive trace gas measurements based on quantum cascade lasers in cw operation," Rev. Sci. Instrum. 76, 075102 (2005).
[CrossRef]

Patel, C. K. N.

M. E. Webber, M. Pushkarsky, and C. K. N. Patel, "Optical detection of chemical warfare agents and toxic industrial chemicals: simulation," J. Appl. Phys. 97, 113101 (2005).
[CrossRef]

M. B. Pushkarsky, M. E. Weber, and C. K. N. Patel, "Ultra-sensitive ambient ammonia detection using CO2 laser based photoacoustic spectroscopy," Appl. Phys. B 77, 381-385 (2003).
[CrossRef]

Peeters, R.

G. Berden, R. Peeters, and G. Meijer, "Cavity ring-down spectroscopy: experimental schemes and applications," Int. Rev. Phys. Chem. 19, 565-607 (2000).
[CrossRef]

Pei, S. S.

G. Luo, C. Peng, H. Q. Le, S. S. Pei, H. Lee, W.-Y. Hwang, B. Ishang, and J. Zheng. "Broadly wavelength-tunable external cavity mid-infrared quantum cascade lasers," IEEE J. Quantum Electron. 38, 486-494 (2002).
[CrossRef]

G. P. Luo, C. Peng, H. Q. Le, S. S. Pei, W.-Y. Hwang, B. Ishaug, J. Um, J. N. Baillargeon, and C.-H. Lin, "Grating-tuned external-cavity quantum-cascade semiconductor lasers," Appl. Phys. Lett. 78, 2834-2836 (2001).
[CrossRef]

Peng, C.

C. Peng, H. L. Zhang, and H. Q. Le, "Mid-infrared external-cavity two-segment quantum-cascade laser," Appl. Phys. Lett. 83, 4098-4100 (2003).
[CrossRef]

C. Peng, G. P. Luo, and H. Q. Le, "Broadband, continuous, and fine-tune properties of external-cavity thermoelectric-stabilized mid-infrared quantum-cascade lasers," Appl. Opt. 42, 4877-4882 (2003).

G. Luo, C. Peng, H. Q. Le, S. S. Pei, H. Lee, W.-Y. Hwang, B. Ishang, and J. Zheng. "Broadly wavelength-tunable external cavity mid-infrared quantum cascade lasers," IEEE J. Quantum Electron. 38, 486-494 (2002).
[CrossRef]

G. P. Luo, C. Peng, H. Q. Le, S. S. Pei, W.-Y. Hwang, B. Ishaug, J. Um, J. N. Baillargeon, and C.-H. Lin, "Grating-tuned external-cavity quantum-cascade semiconductor lasers," Appl. Phys. Lett. 78, 2834-2836 (2001).
[CrossRef]

Petrin, R. R.

Peverall, R.

B. Bakowski, I. Corner, G. Hancock, R. Kotchie, R. Peverall, and G. A. D. Ritchie, "Cavity-enhanced absorption spectroscopy with a rapidly swept diode laser," Appl. Phys. B 75, 745-750 (2002).
[CrossRef]

Pushkarsky, M.

M. E. Webber, M. Pushkarsky, and C. K. N. Patel, "Optical detection of chemical warfare agents and toxic industrial chemicals: simulation," J. Appl. Phys. 97, 113101 (2005).
[CrossRef]

Pushkarsky, M. B.

M. B. Pushkarsky, M. E. Weber, and C. K. N. Patel, "Ultra-sensitive ambient ammonia detection using CO2 laser based photoacoustic spectroscopy," Appl. Phys. B 77, 381-385 (2003).
[CrossRef]

Quagliano, J. R.

Quick, R.

Richter, D. A.

D. C. Senft, M. J. Fox, C. M. Hamilton, D. A. Richter, N. S. Higdon, and B. T. Kelly, "Performance characterization and ground testing of an airborne CO2 differential absorption lidar system (Phase II)," in Laser Radar Technology and Applications IV, G. W. Kamerman and C. Werner, eds. Proc. SPIE 3707, 165-176 (1999).
[CrossRef]

Ritchie, G. A. D.

B. Bakowski, I. Corner, G. Hancock, R. Kotchie, R. Peverall, and G. A. D. Ritchie, "Cavity-enhanced absorption spectroscopy with a rapidly swept diode laser," Appl. Phys. B 75, 745-750 (2002).
[CrossRef]

Romann, A.

M. W. Sigrist, M. Nägele, and A. Romann, "Infrared laser spectroscopy for trace gas analysis," in 4th Iberioamerican Meeting on Optics and 7th Latin American Meeting on Optics, Lasers, and their Applications, V. L. Brudny, S. A. Ledesma, and M. C. Marconi, eds., Proc. SPIE 4419, 14-17 (2001).
[CrossRef]

Romero, R. J.

Rosen, D. I.

M. G. Allen, D. J. Cook, B. K. Decker, J. M. Hensley, D. I. Rosen, M. L. Silva, D. M. Sonnenfroh, and R. T. Wainner, "In-situ and stand-off sensing using QC/IC laser technology from 3-100 microns," in Quantum Sensing and Nanophotonic Devices II, M. Razeghi and G. J. Brown, eds., Proc. SPIE 5732, 134-139 (2005).
[CrossRef]

Sander, R. K.

Senft, D. C.

D. C. Senft, M. J. Fox, C. M. Hamilton, D. A. Richter, N. S. Higdon, and B. T. Kelly, "Performance characterization and ground testing of an airborne CO2 differential absorption lidar system (Phase II)," in Laser Radar Technology and Applications IV, G. W. Kamerman and C. Werner, eds. Proc. SPIE 3707, 165-176 (1999).
[CrossRef]

Shorter, J. H.

D. D. Nelson, J. H. Shorter, J. B. McManus, and M. S. Zahniser, "Sub-part-per-billion detection of nitric oxide in air using a thermoelectrically cooled mid-infrared quantum cascade laser spectrometer," Appl. Phys. B 75, 343-350 (2002).
[CrossRef]

Sigrist, M. W.

M. W. Sigrist, M. Nägele, and A. Romann, "Infrared laser spectroscopy for trace gas analysis," in 4th Iberioamerican Meeting on Optics and 7th Latin American Meeting on Optics, Lasers, and their Applications, V. L. Brudny, S. A. Ledesma, and M. C. Marconi, eds., Proc. SPIE 4419, 14-17 (2001).
[CrossRef]

M. Nagele and M. W. Sigrist, "Mobile laser spectrometer with novel resonant multipass photoacoustic cell for trace-gas sensing," Appl. Phys. B 70, 895-900 (2000).

Silva, M. L.

M. G. Allen, D. J. Cook, B. K. Decker, J. M. Hensley, D. I. Rosen, M. L. Silva, D. M. Sonnenfroh, and R. T. Wainner, "In-situ and stand-off sensing using QC/IC laser technology from 3-100 microns," in Quantum Sensing and Nanophotonic Devices II, M. Razeghi and G. J. Brown, eds., Proc. SPIE 5732, 134-139 (2005).
[CrossRef]

Sivco, D. L.

Sonnenfroh, D. M.

M. G. Allen, D. J. Cook, B. K. Decker, J. M. Hensley, D. I. Rosen, M. L. Silva, D. M. Sonnenfroh, and R. T. Wainner, "In-situ and stand-off sensing using QC/IC laser technology from 3-100 microns," in Quantum Sensing and Nanophotonic Devices II, M. Razeghi and G. J. Brown, eds., Proc. SPIE 5732, 134-139 (2005).
[CrossRef]

Stoutland, P. O.

Swim, C. R.

C. R. Swim, "Review of active chem-bio sensing," in Chemical and Biological Sensing V, P. J. Gardner; ed., Proc. SPIE 5416, 178-185 (2004).
[CrossRef]

Tiee, J. J.

Tittel, F. K.

A. A. Kosterev, Y. A. Bakhirkin, and F. K. Tittel, "Ultrasensitive gas detection by quartz-enhanced photoacoustic spectroscopy in the fundamental molecular absorption bands region," Appl. Phys. B 80, 133-138 (2005).
[CrossRef]

D. Weidmann, F. K. Tittel, T. Aellen, M. Beck, D. Hofstetter, J. Faist, and S. Blaser, "Mid-infrared trace-gas sensing with a quasicontinuous-wave Peltier-cooled distributed feedback quantum cascade laser," Appl. Phys. B 79, 907-913 (2004).
[CrossRef]

Um, J.

G. P. Luo, C. Peng, H. Q. Le, S. S. Pei, W.-Y. Hwang, B. Ishaug, J. Um, J. N. Baillargeon, and C.-H. Lin, "Grating-tuned external-cavity quantum-cascade semiconductor lasers," Appl. Phys. Lett. 78, 2834-2836 (2001).
[CrossRef]

Wainner, R. T.

M. G. Allen, D. J. Cook, B. K. Decker, J. M. Hensley, D. I. Rosen, M. L. Silva, D. M. Sonnenfroh, and R. T. Wainner, "In-situ and stand-off sensing using QC/IC laser technology from 3-100 microns," in Quantum Sensing and Nanophotonic Devices II, M. Razeghi and G. J. Brown, eds., Proc. SPIE 5732, 134-139 (2005).
[CrossRef]

Webber, M. E.

M. E. Webber, M. Pushkarsky, and C. K. N. Patel, "Optical detection of chemical warfare agents and toxic industrial chemicals: simulation," J. Appl. Phys. 97, 113101 (2005).
[CrossRef]

Weber, M. E.

M. B. Pushkarsky, M. E. Weber, and C. K. N. Patel, "Ultra-sensitive ambient ammonia detection using CO2 laser based photoacoustic spectroscopy," Appl. Phys. B 77, 381-385 (2003).
[CrossRef]

Webster, C. R.

R. Q. Yang, C. J. Hill, L. E. Christensen, and C. R. Webster, "Mid-IR type-II interband cascade lasers and their applications," in Semiconductor and Organic Optoelectronic Materials and Devices, C. E. Zah, Y. Luo, and S. Tsuji, eds., Proc. SPIE 5624, 413-422 (2005), and references therein.
[CrossRef]

Weidmann, D.

D. Weidmann, F. K. Tittel, T. Aellen, M. Beck, D. Hofstetter, J. Faist, and S. Blaser, "Mid-infrared trace-gas sensing with a quasicontinuous-wave Peltier-cooled distributed feedback quantum cascade laser," Appl. Phys. B 79, 907-913 (2004).
[CrossRef]

Whitehead, M. C.

Whittaker, E. A.

Yang, R. Q.

C. J. Hill and R. Q. Yang, "MBE growth optimization of Sb-based interband cascade lasers," J. Crys. Growth 278, 167-172 (2005).
[CrossRef]

R. Q. Yang, C. J. Hill, L. E. Christensen, and C. R. Webster, "Mid-IR type-II interband cascade lasers and their applications," in Semiconductor and Organic Optoelectronic Materials and Devices, C. E. Zah, Y. Luo, and S. Tsuji, eds., Proc. SPIE 5624, 413-422 (2005), and references therein.
[CrossRef]

Zahniser, M. S.

D. D. Nelson, J. H. Shorter, J. B. McManus, and M. S. Zahniser, "Sub-part-per-billion detection of nitric oxide in air using a thermoelectrically cooled mid-infrared quantum cascade laser spectrometer," Appl. Phys. B 75, 343-350 (2002).
[CrossRef]

Zhang, H. L.

C. Peng, H. L. Zhang, and H. Q. Le, "Mid-infrared external-cavity two-segment quantum-cascade laser," Appl. Phys. Lett. 83, 4098-4100 (2003).
[CrossRef]

Zheng, J.

G. Luo, C. Peng, H. Q. Le, S. S. Pei, H. Lee, W.-Y. Hwang, B. Ishang, and J. Zheng. "Broadly wavelength-tunable external cavity mid-infrared quantum cascade lasers," IEEE J. Quantum Electron. 38, 486-494 (2002).
[CrossRef]

Appl. Opt. (2)

Appl. Phys. B (7)

M. Nagele and M. W. Sigrist, "Mobile laser spectrometer with novel resonant multipass photoacoustic cell for trace-gas sensing," Appl. Phys. B 70, 895-900 (2000).

M. B. Pushkarsky, M. E. Weber, and C. K. N. Patel, "Ultra-sensitive ambient ammonia detection using CO2 laser based photoacoustic spectroscopy," Appl. Phys. B 77, 381-385 (2003).
[CrossRef]

A. A. Kosterev, Y. A. Bakhirkin, and F. K. Tittel, "Ultrasensitive gas detection by quartz-enhanced photoacoustic spectroscopy in the fundamental molecular absorption bands region," Appl. Phys. B 80, 133-138 (2005).
[CrossRef]

D. D. Nelson, J. H. Shorter, J. B. McManus, and M. S. Zahniser, "Sub-part-per-billion detection of nitric oxide in air using a thermoelectrically cooled mid-infrared quantum cascade laser spectrometer," Appl. Phys. B 75, 343-350 (2002).
[CrossRef]

D. Weidmann, F. K. Tittel, T. Aellen, M. Beck, D. Hofstetter, J. Faist, and S. Blaser, "Mid-infrared trace-gas sensing with a quasicontinuous-wave Peltier-cooled distributed feedback quantum cascade laser," Appl. Phys. B 79, 907-913 (2004).
[CrossRef]

B. Bakowski, I. Corner, G. Hancock, R. Kotchie, R. Peverall, and G. A. D. Ritchie, "Cavity-enhanced absorption spectroscopy with a rapidly swept diode laser," Appl. Phys. B 75, 745-750 (2002).
[CrossRef]

Y. He and B. J. Orr, "Rapid measurement of cavity ringdown absorption spectra with a swept-frequency laser," Appl. Phys. B 79, 941-945 (2004).
[CrossRef]

Appl. Phys. Lett. (2)

C. Peng, H. L. Zhang, and H. Q. Le, "Mid-infrared external-cavity two-segment quantum-cascade laser," Appl. Phys. Lett. 83, 4098-4100 (2003).
[CrossRef]

G. P. Luo, C. Peng, H. Q. Le, S. S. Pei, W.-Y. Hwang, B. Ishaug, J. Um, J. N. Baillargeon, and C.-H. Lin, "Grating-tuned external-cavity quantum-cascade semiconductor lasers," Appl. Phys. Lett. 78, 2834-2836 (2001).
[CrossRef]

IEEE J. Quantum Electron. (1)

G. Luo, C. Peng, H. Q. Le, S. S. Pei, H. Lee, W.-Y. Hwang, B. Ishang, and J. Zheng. "Broadly wavelength-tunable external cavity mid-infrared quantum cascade lasers," IEEE J. Quantum Electron. 38, 486-494 (2002).
[CrossRef]

Int. Rev. Phys. Chem. (1)

G. Berden, R. Peeters, and G. Meijer, "Cavity ring-down spectroscopy: experimental schemes and applications," Int. Rev. Phys. Chem. 19, 565-607 (2000).
[CrossRef]

J. Appl. Phys. (1)

M. E. Webber, M. Pushkarsky, and C. K. N. Patel, "Optical detection of chemical warfare agents and toxic industrial chemicals: simulation," J. Appl. Phys. 97, 113101 (2005).
[CrossRef]

J. Crys. Growth (1)

C. J. Hill and R. Q. Yang, "MBE growth optimization of Sb-based interband cascade lasers," J. Crys. Growth 278, 167-172 (2005).
[CrossRef]

Opt. Lett. (1)

Proc. SPIE (5)

M. W. Sigrist, M. Nägele, and A. Romann, "Infrared laser spectroscopy for trace gas analysis," in 4th Iberioamerican Meeting on Optics and 7th Latin American Meeting on Optics, Lasers, and their Applications, V. L. Brudny, S. A. Ledesma, and M. C. Marconi, eds., Proc. SPIE 4419, 14-17 (2001).
[CrossRef]

D. C. Senft, M. J. Fox, C. M. Hamilton, D. A. Richter, N. S. Higdon, and B. T. Kelly, "Performance characterization and ground testing of an airborne CO2 differential absorption lidar system (Phase II)," in Laser Radar Technology and Applications IV, G. W. Kamerman and C. Werner, eds. Proc. SPIE 3707, 165-176 (1999).
[CrossRef]

C. R. Swim, "Review of active chem-bio sensing," in Chemical and Biological Sensing V, P. J. Gardner; ed., Proc. SPIE 5416, 178-185 (2004).
[CrossRef]

M. G. Allen, D. J. Cook, B. K. Decker, J. M. Hensley, D. I. Rosen, M. L. Silva, D. M. Sonnenfroh, and R. T. Wainner, "In-situ and stand-off sensing using QC/IC laser technology from 3-100 microns," in Quantum Sensing and Nanophotonic Devices II, M. Razeghi and G. J. Brown, eds., Proc. SPIE 5732, 134-139 (2005).
[CrossRef]

R. Q. Yang, C. J. Hill, L. E. Christensen, and C. R. Webster, "Mid-IR type-II interband cascade lasers and their applications," in Semiconductor and Organic Optoelectronic Materials and Devices, C. E. Zah, Y. Luo, and S. Tsuji, eds., Proc. SPIE 5624, 413-422 (2005), and references therein.
[CrossRef]

Rev. Sci. Instrum. (1)

R. Kormann, R. Königstedt, U. Parchatka, J. Lelieveld, and H. Fischer, "QUALITAS: a mid-infrared spectrometer for sensitive trace gas measurements based on quantum cascade lasers in cw operation," Rev. Sci. Instrum. 76, 075102 (2005).
[CrossRef]

Other (2)

See, e.g., D. A. Belsley, E. Kuh, and R. E. Welsch, Regression Diagnostics: Identifying Influential Data and Sources of Collinearity (Wiley, 1980).

See, e.g., G. A. F. Seber and A. J. Lee, Linear Regression Analysis (Wiley, 2003).

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Figures (15)

Fig. 1
Fig. 1

(a), (b) HITRAN-simulated transmission spectra of water and acetylene, respectively. Vertical lines mark the discrete laser wavelengths used for absorption measurements. (c) Close-up view of the spectra, showing overlapped absorption. Some laser lines are not necessarily on the peaks and can be absorbed by both gases.

Fig. 2
Fig. 2

(a) Single-mode output power as a function of wavelength. (b) Normalized wavelength tuned spectra; all with a side-mode suppression ratio of > 20   dB .

Fig. 3
Fig. 3

Absolute calibration of laser wavelength by use of an acetylene line. (a) Acetylene absorption spectrum at low pressure, acquired by taking the power ratio between the two wavelength scans with and without the gas. The wavelength was fine tuned by ramping of the drive current, and the power output varied from 3.1   to   3 .55   mW as shown (the saw-toothed curve). (b) Second-order wavelength modulation spectrum for precision calibration.

Fig. 4
Fig. 4

(a) RIN power spectral density, showing < 110   dB∕Hz , (b) laser frequency noise spectral density.

Fig. 5
Fig. 5

Experimental set up for two-gas absorption measurements. ECLD, electrochemiluminescent detector.

Fig. 6
Fig. 6

Examples of multiwavelength absorption spectra for the four combinations shown.

Fig. 7
Fig. 7

(top) Measured absorption versus linear regression fit for the four spectra in Fig. 6; the R 2 values of the fits are also given. (bottom) Residual errors between observed absorption and fitting results for the four spectra in Fig. 6.

Fig. 8
Fig. 8

(a) Histogram of absorption values for all wavelengths and concentrations. The mean is 0.047. The distribution reflects the randomlike wavelength sampling of many absorption lines with different amplitudes and at different locations on each line. Top inset, relation of absorption value distribution to laser frequency distribution. Bottom inset, model of the probability of an absorption value that is qualitatively similar to the histogram. (b) Histogram of all residual errors, showing a standard deviation of 1.4 % ,   or   7 × 10 −4 in absolute terms.

Fig. 9
Fig. 9

Linear regression results for all 25 combinations of gas concentrations. The acetylene concentration increases from left to right; the water concentration increases from bottom to top. In each figure the filled circle marks the regression-derived concentration. Each ellipse represents a 95 % joint-confidence region, determined by the F-ratio distribution, and a rectangle represents an t-distribution 84 % individual-confidence interval. There is no statistical evidence of interference: both gas concentrations can be determined simultaneously without affecting each other.

Fig. 10
Fig. 10

Comparison of spectroscopically measured concentrations versus experimental settings for (a) acetylene and (b) water.

Fig. 11
Fig. 11

Several wavelength subsets within the original data have been chosen to optimize the 95% joint-confidence ellipse. Ellipse (a) corresponds to the unoptimized full wavelength set. Ellipse (b) (small, solid) represents one of the optimal wavelength subsets. Various dashed ellipses represent other subsets used in the optimization procedure. Although only one concentration is shown, each wavelength set is required for optimizing all 25 measurements shown in Fig. 9.

Fig. 12
Fig. 12

Discrepancy of regression coefficients between the two wavelength sets (a) and (b) in Fig. 11 plotted versus atmospheric optical path length. Linear regression results for this correlation indicate that the probability that the intercept (offset constant) is zero is 92% and that the observed linear slope is zero is 0.0005, suggesting that the discrepancy between the two wavelength sets is unlikely due to random errors. This illustrates the use of statistical analysis to detect unanticipated interference.

Fig. 13
Fig. 13

Sensitivity of regression results to the effect of using a database with incorrect pressure. (top) Variation of absorption coefficients versus pressure for several wavelength positions on a single acetylene absorption line. The pressure-broadening effect appears to be very small, 10 4 , but highly systematic and observable in (bottom): Applying an incorrect 0.2   Torr acetylene database to 0.3 0.5   Torr data produced the dashed ellipses that are larger than the correct-pressure solid ellipses. The increase in error is significant for acetylene concentration, but not for water as expected.

Fig. 14
Fig. 14

Sensitivity of regression results to the effect of using a database with incorrect temperature, represented by a 95% joint-confidence ellipse. The dashed ellipses for 15 °C and 35 °C are clearly much larger than the ellipse at the correct temperature, 23 °C. Temperature can be fitted to within 1 °C by minimizing the ellipse.

Fig. 15
Fig. 15

Effect of error minimization on the ROC. We performed the optimization by searching for wavelength subsets that yield the smallest joint-confidence ellipse as illustrated in Fig. 11. Various ROC curves for hypothetical acetylene detection correspond to the ellipses in Fig. 11, including curves (a) and (b), which correspond to those with the same labels in Fig. 11. The calculation is based on t distribution and uses actual errors from data for a hypothetical acetylene concentration of 0.001   Torr-m . For reference, the dashed curve is the ROC calculation with the same experimental error but based on normal distribution.

Tables (2)

Tables Icon

Table 1 Wavelengths Used for Measurement of Test Points (cm−1)

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Table 2 Quality of Regressions a

Equations (14)

Equations on this page are rendered with MathJax. Learn more.

μ ( λ ) = [ a g 1 ( λ ; P 0 ) a g 2 ( λ ; P 0 ) a g k ( λ ; P 0 ) ] [ b g 1 b g 2 b g k ] ,
α g i ( λ ; P i ) α g i ( λ ; P 0 ) ( P i / P 0 ) ,
[ μ ( λ 1 ) μ ( λ 2 ) μ ( λ n ) ] = [ a g 1 ( λ 1 ) a g 2 ( λ 1 ) a g k ( λ 1 ) a g 1 ( λ 2 ) a g 2 ( λ 2 ) a g k ( λ 2 ) a g 1 ( λ n ) a g 2 ( λ n ) a g k ( λ n ) ] [ b g 1 b g 2 b g k ]
μ = A b ,
b ^ = [ A T A ] 1 A T μ .
Var ( δ b ) Var ( b ^ b ) = [ A T A ] 1 σ 2 ,
b ^ i b i = N { 0 , [ ( A T A ) i i       1 ] 1 / 2 σ } ,
i = 1 , k ,
Var ( δ b ) ( A T A ) 1 σ 2 [ I + u 2 ( A T A ) 1 ] .
μ ( λ ) = ln { exp [ α water ( λ ) L D α acetyl ( λ ) L cell ] }
= α water ( λ ) L D + α acetyl ( λ ) L cell ,
P FAR = P [ b ^ / s ^ t T | b = 0 ] = 1 CDF [ t T ; t ( n k ) ] ,
P Det = P [ b ^ / s ^ t T | b = q ] = 1 CDF   [ t T ( q b ^ ) / s ^ ; t ( n k ) ] ,
P FAR = P [ b ^ > b T | b = 0 ] = 1 CDF [ b T ; N ( 0 , σ ) ] = 1 2 [ 1 erf ( b T σ 2 ) ] ,

Metrics