Abstract

The frequency of a DFB quantum cascade laser (QCL) emitting at 4.3 μm has been long-term stabilized to the Lamb-dip center of a CO2 ro-vibrational transition by means of first-derivative locking to the saturated absorption signal. Thanks to the non-linear sum-frequency generation (SFG) process with a fiber-amplified Nd:YAG laser, the QCL mid-infrared (IR) radiation has been linked to an optical frequency-comb synthesizer (OFCS) and its absolute frequency counted with a kHz-level precision and an overall uncertainty of 75 kHz.

© 2008 Optical Society of America

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  11. L. Diehl, D. Bour, S. Corzine, J. Zhu, G. H¨ofler, M. Loncar, M. Troccoli, and F. Capasso, "High-power quantum cascade lasers grown by low pressure metal organic vapor-phase epitaxy operating in continuous wave above 400 K," Appl. Phys. Lett. 88, 201115 (2006)
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  12. X. J. Wang, J. Y. Fan, T. Tanbun-Ek and F.-S. Choa, "Low threshold quantum cascade lasers of room temperature continuous-wave operation grown by metal-organic chemical-vapor deposition," Appl. Phys. Lett. 90, 211103 (2007)
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  13. S. Blaser, A. B¨achle, S. Jochum, L. Hvozdara, G. Vandeputte, S. Brunner, S. Hansmann, A. Muller and J. Faist, "Low-consumption (below 2 W) continuous-wave single-mode quantum cascade lasers grown by metal-organic vapour-phase epitaxy," Electron. Lett. 43, 1201-1202 (2007)
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  17. M. S. Taubman, T. L. Myers, B. D. Cannon and R. M. Williams, "Stabilization, injection and control of quantum cascade lasers, and their application to chemical sensing in the infrared," Spectrochim. Acta, Part A 60, 3457- 3468 (2004)
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2008 (1)

L. H. Deng, X. M. Gao, Z. S. Cao,W. D. Chen, Y. Q. Yuan,W. J. Zhang and Z. B. Gong, "Widely phase-matched tunable difference-frequency generation in periodically poled LiNbO3 crystal," Opt. Commun. 281, 1686-1692 (2008)
[CrossRef]

2007 (6)

2006 (5)

A. Castrillo, E. De Tommasi, L. Gianfrani, L. Sirigu and J. Faist, "Doppler-free saturated-absorption spectroscopy of CO2 at 4.3 μm by means of a distributed feedback quantum cascade laser," Opt. Lett. 31, 3040-3042 (2006)
[CrossRef] [PubMed]

S. Borri, S. Bartalini, P. De Natale, M. Inguscio, C. Gmachl, F. Capasso, D. L. Sivco and A. Y. Cho, "Frequency modulation spectroscopy by means of quantum cascade lasers," Appl. Phys. B 85, 223-229 (2006)
[CrossRef]

Y. A. Bakhirkin, A. A. Kosterev, R. F. Curl, F. K. Tittel, D. A. Yarekha, L. Hvozdara, M. Giovannini and J. Faist, "Sub-ppbv nitric oxide concentration measurements using cw thermoelectrically cooled quantum cascade laser-based integrated cavity output spectroscopy," Appl. Phys. B 82, 149-154 (2006)
[CrossRef]

L. Diehl, D. Bour, S. Corzine, J. Zhu, G. H¨ofler, M. Loncar, M. Troccoli, and F. Capasso, "High-power quantum cascade lasers grown by low pressure metal organic vapor-phase epitaxy operating in continuous wave above 400 K," Appl. Phys. Lett. 88, 201115 (2006)
[CrossRef]

P. Maddaloni, P. Malara, G. Gagliardi and P. De Natale, "Two-tone frequency modulation spectroscopy for ambient-air trace gas detection using a portable difference-frequency source around 3 μm," Appl. Phys. B 85, 219-222 (2006)
[CrossRef]

2005 (2)

D. Mazzotti, P. Cancio, G. Giusfredi, P. De Natale and M. Prevedelli, "Frequency-comb-based absolute frequency measurements in the mid-infrared with a difference-frequency spectrometer," Opt. Lett. 30, 997-999 (2005)
[CrossRef] [PubMed]

S. Blaser, D. A. Yarekha, L. Hvozdara, Y. Bonetti, A. Muller, M. Giovannini and J. Faist, "Room-temperature, continuous-wave, single-mode quantum cascade lasers at ??? _ 5.4 μm," Appl. Phys. Lett. 86, 041109 (2005)
[CrossRef]

2004 (1)

M. S. Taubman, T. L. Myers, B. D. Cannon and R. M. Williams, "Stabilization, injection and control of quantum cascade lasers, and their application to chemical sensing in the infrared," Spectrochim. Acta, Part A 60, 3457- 3468 (2004)
[CrossRef]

2003 (1)

2002 (5)

2000 (2)

J. T. Remillard, D. Uy,W. H. Weber, F. Capasso, C. Gmachl, A. L. Hutchinson, D. L. Sivco J. N. Baillargeon and A. Y. Cho, "Sub-Doppler resolution limited Lamb-dip spectroscopy of NO with a quantum cascade distributed feedback laser," Opt. Express 7, 243-248 (2000)
[CrossRef] [PubMed]

D. J. Jones, S. A. Diddams, J. K. Ranka, A. Stentz, R. S. Windeler, J. L. Hall and S. T. Cundiff, "Carrier-Envelope Phase Control of Femtosecond Mode-Locked Lasers and Direct Optical Frequency Synthesis," Science 288, 635- 639 (2000)
[CrossRef] [PubMed]

1999 (2)

1996 (1)

B¨achle, A.

S. Blaser, A. B¨achle, S. Jochum, L. Hvozdara, G. Vandeputte, S. Brunner, S. Hansmann, A. Muller and J. Faist, "Low-consumption (below 2 W) continuous-wave single-mode quantum cascade lasers grown by metal-organic vapour-phase epitaxy," Electron. Lett. 43, 1201-1202 (2007)
[CrossRef]

Baillargeon, J. N.

Bakhirkin, Y. A.

Y. A. Bakhirkin, A. A. Kosterev, R. F. Curl, F. K. Tittel, D. A. Yarekha, L. Hvozdara, M. Giovannini and J. Faist, "Sub-ppbv nitric oxide concentration measurements using cw thermoelectrically cooled quantum cascade laser-based integrated cavity output spectroscopy," Appl. Phys. B 82, 149-154 (2006)
[CrossRef]

Bartalini, S.

S. Bartalini, P. Cancio, G. Giusfredi, D. Mazzotti, P. De Natale, S. Borri, I. Galli, T. Leveque and L. Gianfrani, "Frequency-comb-referenced quantum cascade laser at 4.4 μm," Opt. Lett. 32, 988-990 (2007)
[CrossRef] [PubMed]

S. Borri, S. Bartalini, P. De Natale, M. Inguscio, C. Gmachl, F. Capasso, D. L. Sivco and A. Y. Cho, "Frequency modulation spectroscopy by means of quantum cascade lasers," Appl. Phys. B 85, 223-229 (2006)
[CrossRef]

Bielsa, F.

Blaser, S.

A. Mohan, A. Wittmann, A. Hugi, S. Blaser, M. Giovannini and J. Faist, "Room-temperature continuous-wave operation of an external-cavity quantum cascade laser," Opt. Lett. 32, 2792-2794 (2007)
[CrossRef] [PubMed]

S. Blaser, A. B¨achle, S. Jochum, L. Hvozdara, G. Vandeputte, S. Brunner, S. Hansmann, A. Muller and J. Faist, "Low-consumption (below 2 W) continuous-wave single-mode quantum cascade lasers grown by metal-organic vapour-phase epitaxy," Electron. Lett. 43, 1201-1202 (2007)
[CrossRef]

S. Blaser, D. A. Yarekha, L. Hvozdara, Y. Bonetti, A. Muller, M. Giovannini and J. Faist, "Room-temperature, continuous-wave, single-mode quantum cascade lasers at ??? _ 5.4 μm," Appl. Phys. Lett. 86, 041109 (2005)
[CrossRef]

Bonetti, Y.

S. Blaser, D. A. Yarekha, L. Hvozdara, Y. Bonetti, A. Muller, M. Giovannini and J. Faist, "Room-temperature, continuous-wave, single-mode quantum cascade lasers at ??? _ 5.4 μm," Appl. Phys. Lett. 86, 041109 (2005)
[CrossRef]

Borri, S.

Bour, D.

L. Diehl, D. Bour, S. Corzine, J. Zhu, G. H¨ofler, M. Loncar, M. Troccoli, and F. Capasso, "High-power quantum cascade lasers grown by low pressure metal organic vapor-phase epitaxy operating in continuous wave above 400 K," Appl. Phys. Lett. 88, 201115 (2006)
[CrossRef]

Brunner, S.

S. Blaser, A. B¨achle, S. Jochum, L. Hvozdara, G. Vandeputte, S. Brunner, S. Hansmann, A. Muller and J. Faist, "Low-consumption (below 2 W) continuous-wave single-mode quantum cascade lasers grown by metal-organic vapour-phase epitaxy," Electron. Lett. 43, 1201-1202 (2007)
[CrossRef]

Byer, R. L.

Cancio, P.

Cannon, B. D.

M. S. Taubman, T. L. Myers, B. D. Cannon and R. M. Williams, "Stabilization, injection and control of quantum cascade lasers, and their application to chemical sensing in the infrared," Spectrochim. Acta, Part A 60, 3457- 3468 (2004)
[CrossRef]

M. S. Taubman, T. L. Myers, B. D. Cannon, R. M. Williams, F. Capasso, C. Gmachl, D. L. Sivco and A. Y. Cho, "Frequency stabilization of quantum cascade lasers by use of optical cavities," Opt. Lett. 27, 2164-2166 (2002)
[CrossRef]

Cao, Z. S.

L. H. Deng, X. M. Gao, Z. S. Cao,W. D. Chen, Y. Q. Yuan,W. J. Zhang and Z. B. Gong, "Widely phase-matched tunable difference-frequency generation in periodically poled LiNbO3 crystal," Opt. Commun. 281, 1686-1692 (2008)
[CrossRef]

Capasso, F.

L. Diehl, D. Bour, S. Corzine, J. Zhu, G. H¨ofler, M. Loncar, M. Troccoli, and F. Capasso, "High-power quantum cascade lasers grown by low pressure metal organic vapor-phase epitaxy operating in continuous wave above 400 K," Appl. Phys. Lett. 88, 201115 (2006)
[CrossRef]

S. Borri, S. Bartalini, P. De Natale, M. Inguscio, C. Gmachl, F. Capasso, D. L. Sivco and A. Y. Cho, "Frequency modulation spectroscopy by means of quantum cascade lasers," Appl. Phys. B 85, 223-229 (2006)
[CrossRef]

M. S. Taubman, T. L. Myers, B. D. Cannon, R. M. Williams, F. Capasso, C. Gmachl, D. L. Sivco and A. Y. Cho, "Frequency stabilization of quantum cascade lasers by use of optical cavities," Opt. Lett. 27, 2164-2166 (2002)
[CrossRef]

T. L. Myers, R. M. Williams, M. S. Taubman, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon and A. Y. Cho "Free-running frequency stability of mid-infrared quantum cascade lasers," Opt. Lett. 27, 170-172 (2002)
[CrossRef]

J. T. Remillard, D. Uy,W. H. Weber, F. Capasso, C. Gmachl, A. L. Hutchinson, D. L. Sivco J. N. Baillargeon and A. Y. Cho, "Sub-Doppler resolution limited Lamb-dip spectroscopy of NO with a quantum cascade distributed feedback laser," Opt. Express 7, 243-248 (2000)
[CrossRef] [PubMed]

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, and A. Y. Cho, "Kilohertz linewidth from frequency-stabilized mid-infrared quantum cascade lasers," Opt. Lett. 24, 1844-1846 (1999)
[CrossRef]

Casa, G.

Castrillo, A.

Chen, W. D.

L. H. Deng, X. M. Gao, Z. S. Cao,W. D. Chen, Y. Q. Yuan,W. J. Zhang and Z. B. Gong, "Widely phase-matched tunable difference-frequency generation in periodically poled LiNbO3 crystal," Opt. Commun. 281, 1686-1692 (2008)
[CrossRef]

Cho, A. Y.

Choa, F.-S.

X. J. Wang, J. Y. Fan, T. Tanbun-Ek and F.-S. Choa, "Low threshold quantum cascade lasers of room temperature continuous-wave operation grown by metal-organic chemical-vapor deposition," Appl. Phys. Lett. 90, 211103 (2007)
[CrossRef]

Corzine, S.

L. Diehl, D. Bour, S. Corzine, J. Zhu, G. H¨ofler, M. Loncar, M. Troccoli, and F. Capasso, "High-power quantum cascade lasers grown by low pressure metal organic vapor-phase epitaxy operating in continuous wave above 400 K," Appl. Phys. Lett. 88, 201115 (2006)
[CrossRef]

Cundiff, S. T.

D. J. Jones, S. A. Diddams, J. K. Ranka, A. Stentz, R. S. Windeler, J. L. Hall and S. T. Cundiff, "Carrier-Envelope Phase Control of Femtosecond Mode-Locked Lasers and Direct Optical Frequency Synthesis," Science 288, 635- 639 (2000)
[CrossRef] [PubMed]

Curl, R. F.

Y. A. Bakhirkin, A. A. Kosterev, R. F. Curl, F. K. Tittel, D. A. Yarekha, L. Hvozdara, M. Giovannini and J. Faist, "Sub-ppbv nitric oxide concentration measurements using cw thermoelectrically cooled quantum cascade laser-based integrated cavity output spectroscopy," Appl. Phys. B 82, 149-154 (2006)
[CrossRef]

De Natale, P.

S. Bartalini, P. Cancio, G. Giusfredi, D. Mazzotti, P. De Natale, S. Borri, I. Galli, T. Leveque and L. Gianfrani, "Frequency-comb-referenced quantum cascade laser at 4.4 μm," Opt. Lett. 32, 988-990 (2007)
[CrossRef] [PubMed]

S. Borri, S. Bartalini, P. De Natale, M. Inguscio, C. Gmachl, F. Capasso, D. L. Sivco and A. Y. Cho, "Frequency modulation spectroscopy by means of quantum cascade lasers," Appl. Phys. B 85, 223-229 (2006)
[CrossRef]

P. Maddaloni, P. Malara, G. Gagliardi and P. De Natale, "Two-tone frequency modulation spectroscopy for ambient-air trace gas detection using a portable difference-frequency source around 3 μm," Appl. Phys. B 85, 219-222 (2006)
[CrossRef]

D. Mazzotti, P. Cancio, G. Giusfredi, P. De Natale and M. Prevedelli, "Frequency-comb-based absolute frequency measurements in the mid-infrared with a difference-frequency spectrometer," Opt. Lett. 30, 997-999 (2005)
[CrossRef] [PubMed]

D. Mazzotti, G. Giusfredi, P. Cancio and P. De Natale, "High-sensitivity spectroscopy of CO2 around 4.25 μm with difference-frequency radiation," Opt. Lasers Eng. 37, 143-158 (2002)
[CrossRef]

D. Mazzotti, S. Borri, P. Cancio, G. Giusfredi and P. De Natale, "Low-power Lamb-dip spectroscopy of very weak CO2 transitions near 4.25 μm," Opt. Lett. 27, 1256-1258 (2002)
[CrossRef]

De Tommasi, E.

Deng, L. H.

L. H. Deng, X. M. Gao, Z. S. Cao,W. D. Chen, Y. Q. Yuan,W. J. Zhang and Z. B. Gong, "Widely phase-matched tunable difference-frequency generation in periodically poled LiNbO3 crystal," Opt. Commun. 281, 1686-1692 (2008)
[CrossRef]

Diddams, S. A.

D. J. Jones, S. A. Diddams, J. K. Ranka, A. Stentz, R. S. Windeler, J. L. Hall and S. T. Cundiff, "Carrier-Envelope Phase Control of Femtosecond Mode-Locked Lasers and Direct Optical Frequency Synthesis," Science 288, 635- 639 (2000)
[CrossRef] [PubMed]

Diehl, L.

L. Diehl, D. Bour, S. Corzine, J. Zhu, G. H¨ofler, M. Loncar, M. Troccoli, and F. Capasso, "High-power quantum cascade lasers grown by low pressure metal organic vapor-phase epitaxy operating in continuous wave above 400 K," Appl. Phys. Lett. 88, 201115 (2006)
[CrossRef]

Douillet, A.

Eckardt, R. C.

Faist, J.

S. Blaser, A. B¨achle, S. Jochum, L. Hvozdara, G. Vandeputte, S. Brunner, S. Hansmann, A. Muller and J. Faist, "Low-consumption (below 2 W) continuous-wave single-mode quantum cascade lasers grown by metal-organic vapour-phase epitaxy," Electron. Lett. 43, 1201-1202 (2007)
[CrossRef]

A. Mohan, A. Wittmann, A. Hugi, S. Blaser, M. Giovannini and J. Faist, "Room-temperature continuous-wave operation of an external-cavity quantum cascade laser," Opt. Lett. 32, 2792-2794 (2007)
[CrossRef] [PubMed]

A. Castrillo, E. De Tommasi, L. Gianfrani, L. Sirigu and J. Faist, "Doppler-free saturated-absorption spectroscopy of CO2 at 4.3 μm by means of a distributed feedback quantum cascade laser," Opt. Lett. 31, 3040-3042 (2006)
[CrossRef] [PubMed]

Y. A. Bakhirkin, A. A. Kosterev, R. F. Curl, F. K. Tittel, D. A. Yarekha, L. Hvozdara, M. Giovannini and J. Faist, "Sub-ppbv nitric oxide concentration measurements using cw thermoelectrically cooled quantum cascade laser-based integrated cavity output spectroscopy," Appl. Phys. B 82, 149-154 (2006)
[CrossRef]

S. Blaser, D. A. Yarekha, L. Hvozdara, Y. Bonetti, A. Muller, M. Giovannini and J. Faist, "Room-temperature, continuous-wave, single-mode quantum cascade lasers at ??? _ 5.4 μm," Appl. Phys. Lett. 86, 041109 (2005)
[CrossRef]

Fan, J. Y.

X. J. Wang, J. Y. Fan, T. Tanbun-Ek and F.-S. Choa, "Low threshold quantum cascade lasers of room temperature continuous-wave operation grown by metal-organic chemical-vapor deposition," Appl. Phys. Lett. 90, 211103 (2007)
[CrossRef]

Fejer, M. M.

Foreman, S. M.

Gagliardi, G.

P. Maddaloni, P. Malara, G. Gagliardi and P. De Natale, "Two-tone frequency modulation spectroscopy for ambient-air trace gas detection using a portable difference-frequency source around 3 μm," Appl. Phys. B 85, 219-222 (2006)
[CrossRef]

Galli, I.

Gao, X. M.

L. H. Deng, X. M. Gao, Z. S. Cao,W. D. Chen, Y. Q. Yuan,W. J. Zhang and Z. B. Gong, "Widely phase-matched tunable difference-frequency generation in periodically poled LiNbO3 crystal," Opt. Commun. 281, 1686-1692 (2008)
[CrossRef]

Gianfrani, L.

Giovannini, M.

A. Mohan, A. Wittmann, A. Hugi, S. Blaser, M. Giovannini and J. Faist, "Room-temperature continuous-wave operation of an external-cavity quantum cascade laser," Opt. Lett. 32, 2792-2794 (2007)
[CrossRef] [PubMed]

Y. A. Bakhirkin, A. A. Kosterev, R. F. Curl, F. K. Tittel, D. A. Yarekha, L. Hvozdara, M. Giovannini and J. Faist, "Sub-ppbv nitric oxide concentration measurements using cw thermoelectrically cooled quantum cascade laser-based integrated cavity output spectroscopy," Appl. Phys. B 82, 149-154 (2006)
[CrossRef]

S. Blaser, D. A. Yarekha, L. Hvozdara, Y. Bonetti, A. Muller, M. Giovannini and J. Faist, "Room-temperature, continuous-wave, single-mode quantum cascade lasers at ??? _ 5.4 μm," Appl. Phys. Lett. 86, 041109 (2005)
[CrossRef]

Giusfredi, G.

Gmachl, C.

Gong, Z. B.

L. H. Deng, X. M. Gao, Z. S. Cao,W. D. Chen, Y. Q. Yuan,W. J. Zhang and Z. B. Gong, "Widely phase-matched tunable difference-frequency generation in periodically poled LiNbO3 crystal," Opt. Commun. 281, 1686-1692 (2008)
[CrossRef]

H¨ansch, T.W.

T. Udem, J. Reichert, R. Holzwarth and T.W. H¨ansch, "Absolute Optical Frequency Measurement of the Cesium D1 Line with a Mode-Locked Laser," Phys. Rev. Lett. 82, 3568-3571 (1999)
[CrossRef]

H¨ofler, G.

L. Diehl, D. Bour, S. Corzine, J. Zhu, G. H¨ofler, M. Loncar, M. Troccoli, and F. Capasso, "High-power quantum cascade lasers grown by low pressure metal organic vapor-phase epitaxy operating in continuous wave above 400 K," Appl. Phys. Lett. 88, 201115 (2006)
[CrossRef]

Hall, J. L.

D. J. Jones, S. A. Diddams, J. K. Ranka, A. Stentz, R. S. Windeler, J. L. Hall and S. T. Cundiff, "Carrier-Envelope Phase Control of Femtosecond Mode-Locked Lasers and Direct Optical Frequency Synthesis," Science 288, 635- 639 (2000)
[CrossRef] [PubMed]

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, and A. Y. Cho, "Kilohertz linewidth from frequency-stabilized mid-infrared quantum cascade lasers," Opt. Lett. 24, 1844-1846 (1999)
[CrossRef]

Hansmann, S.

S. Blaser, A. B¨achle, S. Jochum, L. Hvozdara, G. Vandeputte, S. Brunner, S. Hansmann, A. Muller and J. Faist, "Low-consumption (below 2 W) continuous-wave single-mode quantum cascade lasers grown by metal-organic vapour-phase epitaxy," Electron. Lett. 43, 1201-1202 (2007)
[CrossRef]

Hartman, J. S.

Hilico, L.

Holzwarth, R.

T. Udem, J. Reichert, R. Holzwarth and T.W. H¨ansch, "Absolute Optical Frequency Measurement of the Cesium D1 Line with a Mode-Locked Laser," Phys. Rev. Lett. 82, 3568-3571 (1999)
[CrossRef]

Hugi, A.

Hutchinson, A. L.

Hvozdara, L.

S. Blaser, A. B¨achle, S. Jochum, L. Hvozdara, G. Vandeputte, S. Brunner, S. Hansmann, A. Muller and J. Faist, "Low-consumption (below 2 W) continuous-wave single-mode quantum cascade lasers grown by metal-organic vapour-phase epitaxy," Electron. Lett. 43, 1201-1202 (2007)
[CrossRef]

Y. A. Bakhirkin, A. A. Kosterev, R. F. Curl, F. K. Tittel, D. A. Yarekha, L. Hvozdara, M. Giovannini and J. Faist, "Sub-ppbv nitric oxide concentration measurements using cw thermoelectrically cooled quantum cascade laser-based integrated cavity output spectroscopy," Appl. Phys. B 82, 149-154 (2006)
[CrossRef]

S. Blaser, D. A. Yarekha, L. Hvozdara, Y. Bonetti, A. Muller, M. Giovannini and J. Faist, "Room-temperature, continuous-wave, single-mode quantum cascade lasers at ??? _ 5.4 μm," Appl. Phys. Lett. 86, 041109 (2005)
[CrossRef]

Inguscio, M.

S. Borri, S. Bartalini, P. De Natale, M. Inguscio, C. Gmachl, F. Capasso, D. L. Sivco and A. Y. Cho, "Frequency modulation spectroscopy by means of quantum cascade lasers," Appl. Phys. B 85, 223-229 (2006)
[CrossRef]

Jochum, S.

S. Blaser, A. B¨achle, S. Jochum, L. Hvozdara, G. Vandeputte, S. Brunner, S. Hansmann, A. Muller and J. Faist, "Low-consumption (below 2 W) continuous-wave single-mode quantum cascade lasers grown by metal-organic vapour-phase epitaxy," Electron. Lett. 43, 1201-1202 (2007)
[CrossRef]

Jones, D. J.

S. M. Foreman, D. J. Jones and J. Ye, "Flexible and rapidly configurable femtosecond pulse generation in the mid-IR," Opt. Lett. 28, 370-372 (2003)
[CrossRef] [PubMed]

D. J. Jones, S. A. Diddams, J. K. Ranka, A. Stentz, R. S. Windeler, J. L. Hall and S. T. Cundiff, "Carrier-Envelope Phase Control of Femtosecond Mode-Locked Lasers and Direct Optical Frequency Synthesis," Science 288, 635- 639 (2000)
[CrossRef] [PubMed]

Karr, J.

Kelly, J. F.

Kosterev, A. A.

Y. A. Bakhirkin, A. A. Kosterev, R. F. Curl, F. K. Tittel, D. A. Yarekha, L. Hvozdara, M. Giovannini and J. Faist, "Sub-ppbv nitric oxide concentration measurements using cw thermoelectrically cooled quantum cascade laser-based integrated cavity output spectroscopy," Appl. Phys. B 82, 149-154 (2006)
[CrossRef]

Leveque, T.

Lipphardt, B.

H. R. Telle, B. Lipphardt and J. Stenger, "Kerr-lens mode-locked lasers as transfer oscillators for optical frequency measurements," Appl. Phys. B 74, 1-6 (2002)
[CrossRef]

Loncar, M.

L. Diehl, D. Bour, S. Corzine, J. Zhu, G. H¨ofler, M. Loncar, M. Troccoli, and F. Capasso, "High-power quantum cascade lasers grown by low pressure metal organic vapor-phase epitaxy operating in continuous wave above 400 K," Appl. Phys. Lett. 88, 201115 (2006)
[CrossRef]

Maddaloni, P.

P. Maddaloni, P. Malara, G. Gagliardi and P. De Natale, "Two-tone frequency modulation spectroscopy for ambient-air trace gas detection using a portable difference-frequency source around 3 μm," Appl. Phys. B 85, 219-222 (2006)
[CrossRef]

Malara, P.

P. Maddaloni, P. Malara, G. Gagliardi and P. De Natale, "Two-tone frequency modulation spectroscopy for ambient-air trace gas detection using a portable difference-frequency source around 3 μm," Appl. Phys. B 85, 219-222 (2006)
[CrossRef]

Mazzotti, D.

Mohan, A.

Muller, A.

S. Blaser, A. B¨achle, S. Jochum, L. Hvozdara, G. Vandeputte, S. Brunner, S. Hansmann, A. Muller and J. Faist, "Low-consumption (below 2 W) continuous-wave single-mode quantum cascade lasers grown by metal-organic vapour-phase epitaxy," Electron. Lett. 43, 1201-1202 (2007)
[CrossRef]

S. Blaser, D. A. Yarekha, L. Hvozdara, Y. Bonetti, A. Muller, M. Giovannini and J. Faist, "Room-temperature, continuous-wave, single-mode quantum cascade lasers at ??? _ 5.4 μm," Appl. Phys. Lett. 86, 041109 (2005)
[CrossRef]

Myers, L. E.

Myers, T. L.

Prevedelli, M.

Ranka, J. K.

D. J. Jones, S. A. Diddams, J. K. Ranka, A. Stentz, R. S. Windeler, J. L. Hall and S. T. Cundiff, "Carrier-Envelope Phase Control of Femtosecond Mode-Locked Lasers and Direct Optical Frequency Synthesis," Science 288, 635- 639 (2000)
[CrossRef] [PubMed]

Reichert, J.

T. Udem, J. Reichert, R. Holzwarth and T.W. H¨ansch, "Absolute Optical Frequency Measurement of the Cesium D1 Line with a Mode-Locked Laser," Phys. Rev. Lett. 82, 3568-3571 (1999)
[CrossRef]

Remillard, J. T.

Sharpe, S. W.

Sirigu, L.

Sivco, D. L.

Stenger, J.

H. R. Telle, B. Lipphardt and J. Stenger, "Kerr-lens mode-locked lasers as transfer oscillators for optical frequency measurements," Appl. Phys. B 74, 1-6 (2002)
[CrossRef]

Stentz, A.

D. J. Jones, S. A. Diddams, J. K. Ranka, A. Stentz, R. S. Windeler, J. L. Hall and S. T. Cundiff, "Carrier-Envelope Phase Control of Femtosecond Mode-Locked Lasers and Direct Optical Frequency Synthesis," Science 288, 635- 639 (2000)
[CrossRef] [PubMed]

Tanbun-Ek, T.

X. J. Wang, J. Y. Fan, T. Tanbun-Ek and F.-S. Choa, "Low threshold quantum cascade lasers of room temperature continuous-wave operation grown by metal-organic chemical-vapor deposition," Appl. Phys. Lett. 90, 211103 (2007)
[CrossRef]

Taubman, M. S.

Telle, H. R.

H. R. Telle, B. Lipphardt and J. Stenger, "Kerr-lens mode-locked lasers as transfer oscillators for optical frequency measurements," Appl. Phys. B 74, 1-6 (2002)
[CrossRef]

Tittel, F. K.

Y. A. Bakhirkin, A. A. Kosterev, R. F. Curl, F. K. Tittel, D. A. Yarekha, L. Hvozdara, M. Giovannini and J. Faist, "Sub-ppbv nitric oxide concentration measurements using cw thermoelectrically cooled quantum cascade laser-based integrated cavity output spectroscopy," Appl. Phys. B 82, 149-154 (2006)
[CrossRef]

Troccoli, M.

L. Diehl, D. Bour, S. Corzine, J. Zhu, G. H¨ofler, M. Loncar, M. Troccoli, and F. Capasso, "High-power quantum cascade lasers grown by low pressure metal organic vapor-phase epitaxy operating in continuous wave above 400 K," Appl. Phys. Lett. 88, 201115 (2006)
[CrossRef]

Udem, T.

T. Udem, J. Reichert, R. Holzwarth and T.W. H¨ansch, "Absolute Optical Frequency Measurement of the Cesium D1 Line with a Mode-Locked Laser," Phys. Rev. Lett. 82, 3568-3571 (1999)
[CrossRef]

Uy, D.

Valenzuela, T.

Vandeputte, G.

S. Blaser, A. B¨achle, S. Jochum, L. Hvozdara, G. Vandeputte, S. Brunner, S. Hansmann, A. Muller and J. Faist, "Low-consumption (below 2 W) continuous-wave single-mode quantum cascade lasers grown by metal-organic vapour-phase epitaxy," Electron. Lett. 43, 1201-1202 (2007)
[CrossRef]

Wang, X. J.

X. J. Wang, J. Y. Fan, T. Tanbun-Ek and F.-S. Choa, "Low threshold quantum cascade lasers of room temperature continuous-wave operation grown by metal-organic chemical-vapor deposition," Appl. Phys. Lett. 90, 211103 (2007)
[CrossRef]

Weber, W. H.

Williams, R. M.

Windeler, R. S.

D. J. Jones, S. A. Diddams, J. K. Ranka, A. Stentz, R. S. Windeler, J. L. Hall and S. T. Cundiff, "Carrier-Envelope Phase Control of Femtosecond Mode-Locked Lasers and Direct Optical Frequency Synthesis," Science 288, 635- 639 (2000)
[CrossRef] [PubMed]

Wittmann, A.

Yarekha, D. A.

Y. A. Bakhirkin, A. A. Kosterev, R. F. Curl, F. K. Tittel, D. A. Yarekha, L. Hvozdara, M. Giovannini and J. Faist, "Sub-ppbv nitric oxide concentration measurements using cw thermoelectrically cooled quantum cascade laser-based integrated cavity output spectroscopy," Appl. Phys. B 82, 149-154 (2006)
[CrossRef]

S. Blaser, D. A. Yarekha, L. Hvozdara, Y. Bonetti, A. Muller, M. Giovannini and J. Faist, "Room-temperature, continuous-wave, single-mode quantum cascade lasers at ??? _ 5.4 μm," Appl. Phys. Lett. 86, 041109 (2005)
[CrossRef]

Ye, J.

Yuan, Y. Q.

L. H. Deng, X. M. Gao, Z. S. Cao,W. D. Chen, Y. Q. Yuan,W. J. Zhang and Z. B. Gong, "Widely phase-matched tunable difference-frequency generation in periodically poled LiNbO3 crystal," Opt. Commun. 281, 1686-1692 (2008)
[CrossRef]

Zhang, W. J.

L. H. Deng, X. M. Gao, Z. S. Cao,W. D. Chen, Y. Q. Yuan,W. J. Zhang and Z. B. Gong, "Widely phase-matched tunable difference-frequency generation in periodically poled LiNbO3 crystal," Opt. Commun. 281, 1686-1692 (2008)
[CrossRef]

Zhu, J.

L. Diehl, D. Bour, S. Corzine, J. Zhu, G. H¨ofler, M. Loncar, M. Troccoli, and F. Capasso, "High-power quantum cascade lasers grown by low pressure metal organic vapor-phase epitaxy operating in continuous wave above 400 K," Appl. Phys. Lett. 88, 201115 (2006)
[CrossRef]

Appl. Phys. B (4)

P. Maddaloni, P. Malara, G. Gagliardi and P. De Natale, "Two-tone frequency modulation spectroscopy for ambient-air trace gas detection using a portable difference-frequency source around 3 μm," Appl. Phys. B 85, 219-222 (2006)
[CrossRef]

Y. A. Bakhirkin, A. A. Kosterev, R. F. Curl, F. K. Tittel, D. A. Yarekha, L. Hvozdara, M. Giovannini and J. Faist, "Sub-ppbv nitric oxide concentration measurements using cw thermoelectrically cooled quantum cascade laser-based integrated cavity output spectroscopy," Appl. Phys. B 82, 149-154 (2006)
[CrossRef]

S. Borri, S. Bartalini, P. De Natale, M. Inguscio, C. Gmachl, F. Capasso, D. L. Sivco and A. Y. Cho, "Frequency modulation spectroscopy by means of quantum cascade lasers," Appl. Phys. B 85, 223-229 (2006)
[CrossRef]

H. R. Telle, B. Lipphardt and J. Stenger, "Kerr-lens mode-locked lasers as transfer oscillators for optical frequency measurements," Appl. Phys. B 74, 1-6 (2002)
[CrossRef]

Appl. Phys. Lett. (3)

S. Blaser, D. A. Yarekha, L. Hvozdara, Y. Bonetti, A. Muller, M. Giovannini and J. Faist, "Room-temperature, continuous-wave, single-mode quantum cascade lasers at ??? _ 5.4 μm," Appl. Phys. Lett. 86, 041109 (2005)
[CrossRef]

L. Diehl, D. Bour, S. Corzine, J. Zhu, G. H¨ofler, M. Loncar, M. Troccoli, and F. Capasso, "High-power quantum cascade lasers grown by low pressure metal organic vapor-phase epitaxy operating in continuous wave above 400 K," Appl. Phys. Lett. 88, 201115 (2006)
[CrossRef]

X. J. Wang, J. Y. Fan, T. Tanbun-Ek and F.-S. Choa, "Low threshold quantum cascade lasers of room temperature continuous-wave operation grown by metal-organic chemical-vapor deposition," Appl. Phys. Lett. 90, 211103 (2007)
[CrossRef]

Electron. Lett. (1)

S. Blaser, A. B¨achle, S. Jochum, L. Hvozdara, G. Vandeputte, S. Brunner, S. Hansmann, A. Muller and J. Faist, "Low-consumption (below 2 W) continuous-wave single-mode quantum cascade lasers grown by metal-organic vapour-phase epitaxy," Electron. Lett. 43, 1201-1202 (2007)
[CrossRef]

Opt. Commun. (1)

L. H. Deng, X. M. Gao, Z. S. Cao,W. D. Chen, Y. Q. Yuan,W. J. Zhang and Z. B. Gong, "Widely phase-matched tunable difference-frequency generation in periodically poled LiNbO3 crystal," Opt. Commun. 281, 1686-1692 (2008)
[CrossRef]

Opt. Express (1)

Opt. Lasers Eng. (1)

D. Mazzotti, G. Giusfredi, P. Cancio and P. De Natale, "High-sensitivity spectroscopy of CO2 around 4.25 μm with difference-frequency radiation," Opt. Lasers Eng. 37, 143-158 (2002)
[CrossRef]

Opt. Lett. (12)

D. Mazzotti, S. Borri, P. Cancio, G. Giusfredi and P. De Natale, "Low-power Lamb-dip spectroscopy of very weak CO2 transitions near 4.25 μm," Opt. Lett. 27, 1256-1258 (2002)
[CrossRef]

L. E. Myers, R. C. Eckardt, M. M. Fejer and R. L. Byer, "Multigrating quasi-phase-matched optical parametric oscillator in periodically poled LiNbO3," Opt. Lett. 21, 591-593 (1996)
[CrossRef] [PubMed]

S. M. Foreman, D. J. Jones and J. Ye, "Flexible and rapidly configurable femtosecond pulse generation in the mid-IR," Opt. Lett. 28, 370-372 (2003)
[CrossRef] [PubMed]

D. Mazzotti, P. Cancio, G. Giusfredi, P. De Natale and M. Prevedelli, "Frequency-comb-based absolute frequency measurements in the mid-infrared with a difference-frequency spectrometer," Opt. Lett. 30, 997-999 (2005)
[CrossRef] [PubMed]

A. Mohan, A. Wittmann, A. Hugi, S. Blaser, M. Giovannini and J. Faist, "Room-temperature continuous-wave operation of an external-cavity quantum cascade laser," Opt. Lett. 32, 2792-2794 (2007)
[CrossRef] [PubMed]

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, and A. Y. Cho, "Kilohertz linewidth from frequency-stabilized mid-infrared quantum cascade lasers," Opt. Lett. 24, 1844-1846 (1999)
[CrossRef]

M. S. Taubman, T. L. Myers, B. D. Cannon, R. M. Williams, F. Capasso, C. Gmachl, D. L. Sivco and A. Y. Cho, "Frequency stabilization of quantum cascade lasers by use of optical cavities," Opt. Lett. 27, 2164-2166 (2002)
[CrossRef]

A. Castrillo, E. De Tommasi, L. Gianfrani, L. Sirigu and J. Faist, "Doppler-free saturated-absorption spectroscopy of CO2 at 4.3 μm by means of a distributed feedback quantum cascade laser," Opt. Lett. 31, 3040-3042 (2006)
[CrossRef] [PubMed]

A. Castrillo, G. Casa and L. Gianfrani, "Oxygen isotope ratio measurements in CO2 by means of a continuouswave quantum cascade laser at 4.3 μm," Opt. Lett. 32, 3047-3049 (2007)
[CrossRef] [PubMed]

S. Bartalini, P. Cancio, G. Giusfredi, D. Mazzotti, P. De Natale, S. Borri, I. Galli, T. Leveque and L. Gianfrani, "Frequency-comb-referenced quantum cascade laser at 4.4 μm," Opt. Lett. 32, 988-990 (2007)
[CrossRef] [PubMed]

F. Bielsa, A. Douillet, T. Valenzuela, J. Karr, and L. Hilico, "Narrow-line phase-locked quantum cascade laser in the 9.2 μm range," Opt. Lett. 32, 1641-1643 (2007)
[CrossRef] [PubMed]

T. L. Myers, R. M. Williams, M. S. Taubman, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon and A. Y. Cho "Free-running frequency stability of mid-infrared quantum cascade lasers," Opt. Lett. 27, 170-172 (2002)
[CrossRef]

Phys. Rev. Lett. (1)

T. Udem, J. Reichert, R. Holzwarth and T.W. H¨ansch, "Absolute Optical Frequency Measurement of the Cesium D1 Line with a Mode-Locked Laser," Phys. Rev. Lett. 82, 3568-3571 (1999)
[CrossRef]

Science (1)

D. J. Jones, S. A. Diddams, J. K. Ranka, A. Stentz, R. S. Windeler, J. L. Hall and S. T. Cundiff, "Carrier-Envelope Phase Control of Femtosecond Mode-Locked Lasers and Direct Optical Frequency Synthesis," Science 288, 635- 639 (2000)
[CrossRef] [PubMed]

Spectrochim. Acta, Part A (1)

M. S. Taubman, T. L. Myers, B. D. Cannon and R. M. Williams, "Stabilization, injection and control of quantum cascade lasers, and their application to chemical sensing in the infrared," Spectrochim. Acta, Part A 60, 3457- 3468 (2004)
[CrossRef]

Other (3)

P. Rabinowitz, R. Keller and J. T. Latourrette, "Frequency stabilization of CO2 lasers with respect to SF6 and CO2 line centers," in 24th Annual Symposium on Frequency Control,, pp. 275-278, (1970)

The HITRAN database is available at http://cfa-www.harvard.edu/HITRAN

V. S. Letokhov, Saturation spectroscopy, in High-Resolution Laser Spectroscopy, K. Shimoda, ed. (Springer, 1976), pp. 96-171

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Figures (6)

Fig. 1.
Fig. 1.

Schematic of the experimental set-up. In the figure the main blocks of the apparatus have been highlighted by dashed lines: the QCL housing and collimation (a), the saturation spectroscopy set-up (b), the SFG assembly (c), the near-IR lasers phase-locked to the comb (d) and the beat-note detection and measurement (e). P1 and P2 are wire grid polarizers, T-λ/2 is a tunable half-waveplate and BS is a beam-splitter.

Fig. 2.
Fig. 2.

Saturation spectrum of the (0111-0110) P(30) CO2 transition in direct-absorption (a) and first-derivative detection (b). The gas pressure in the cell was 20 mTorr (which brings to a relative absorption of about 10%) and the pump intensity interacting with the gas sample was about a factor 2 greater than the saturation level. The two traces have been recorded by a digital scope, with a sweeping time of about 0.2 seconds. The first-derivative signal was obtained by a lock-in amplifier with 1 ms integration time constant. The best fit and residuals are also shown.

Fig. 3.
Fig. 3.

(a) QCL noise power spectral density in free-running (red trace) and locking (black trace) conditions, obtained by using the slope of a germanium-etalon transmission fringe as a frequency discriminator. (b) The lock-in output signal qualitatively shows the frequency fluctuations that can be compensated by the loop.

Fig. 4.
Fig. 4.

Power spectral density of the beat-note between the SFG and the diode laser radiation recorded with a real-time spectrum analyzer. The acquisition lengths are 70 ms (black Gaussian profile) and 70 μs (grey line). A Gaussian function has been fitted to the black spectrum and the obtained HWHM is 5.3 MHz.

Fig. 5.
Fig. 5.

(a) Comparison between the spreads of the beat-note frequency values as measured by the counter in free-running and locked conditions. (b) 20-minutes-long acquisition of the beat-note frequency, shown in a 100× zoomed scale. The right part of the figure shows the frequency distribution of the data: a Gaussian fit is superimposed and the resulting 2 kHz standard deviation of the mean can be assumed as the precision of this measurement.

Fig. 6.
Fig. 6.

All the measured beat-note frequencies are reported in this figure. Each point corresponds to the mean value of a long-time acquisition (as that shown in Fig. 5), with its uncertainty (standard deviation of the mean). The mean value and standard deviation of the data are also shown (red line and grey area, respectively).

Equations (2)

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

v C = v D v Y + Δ v ,
v C = 69267227.764 ( 75 ) MHz

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