Abstract

We present a novel approach for the reversible switching of the emission wavelength of a quantum cascade laser (QCL) using a halochromic cladding. An air-waveguide laser ridge is coated with a thin layer of polyacrylic acid. This cladding introduces losses corresponding to the absorption spectrum of the polymer. By changing the state of the polymer, the absorption spectrum and losses change, inducing a shift of 7 cm-1 in the emission wavelength. This change is induced by exposure to acidic or alkaline vapors under ambient conditions and is fully reversible. Such lasers can be used as multi-color light source and as sensor for atmospheric pH.

© 2008 Optical Society of America

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    [CrossRef] [PubMed]
  4. D. Barate, R. Teissier, Y. Wang, and A. N. Baranov, "Short wavelength intersubband emission from InAs/AlSb quantum cascade structures," Appl. Phys. Lett. 87, 051103 (2005).
    [CrossRef]
  5. J. Ulrich, J. Kreuter, W. Schrenk, G. Strasser, and K. Unterrainer, "Long wavelength (15 and 23 µm) GaAs/AlGaAs quantum cascade lasers," Appl. Phys. Lett. 80, 3691-3693 (2002).
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  7. M. A. Belkin, F. Capasso, A. Belyanin, D. L. Sivco, A. Y. Cho, D. C. Oakley, C. J. Vineis, and G. W. Turner, "Terahertz quantum-cascade-laser source based on intracavity difference-frequency generation," Nat. Photon. 1, 288-292 (2007).
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  8. J. Faist, C. Gmachl, F. Capasso, C. Sirtori, C. L. Sivco, J. N. Baillargeon, and A. Y. Cho, "Distributed feedback quantum cascade lasers," Appl. Phys. Lett. 70, 2670-2672(1997).
    [CrossRef]
  9. C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
    [CrossRef]
  10. R. Colombelli, K. Srinivasan, M. Troccoli, O. Painter, C. F. Gmachl, D. M. Tennant, A. M. Sergent, D. L. Sivco, and A. Y. Cho, F. Capasso, "Quantum Cascade Surface-Emitting Photonic Crystal Laser," Science 302, 1374-1377 (2003).
    [CrossRef] [PubMed]
  11. C. Pflügl, W. Schrenk, S. Anders, and G. Strasser, "Spectral dynamics of distributed feedback quantum cascade lasers," Semicond. Sci. Technol. 19, S336-S338 (2004).
    [CrossRef]
  12. S. Song, S. S. Howard, Z. Liu, A. O. Dirisu, C. F. Gmachl, and C. B. Arnold, "Mode tuning of quantum cascade lasers through optical processing of chalcogenide glass claddings," Appl. Phys. Lett. 89, 041115 (2006).
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    [CrossRef]
  20. D. Hofstetter, J. Faist, M. Beck, and U. Oesterle, "Surface-emitting 10.1 µm quantum-cascade distributed feedback lasers," Appl. Phys. Lett. 75, 3769-3771 (1999).
    [CrossRef]
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    [CrossRef]
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    [CrossRef]
  33. K. Dioumaev, "Infrared methods for monitoring the protonation state of carboxylic amino acids in the photocycle of bacteriorhodopsin," Biochemistry (Moscow) 66, 1269-1276 (2001).
    [CrossRef]
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    [CrossRef]

2008

J. Schenk, I. W. Marison, and U. von Stockar, "pH prediction and control in bioprocesses using mid-infrared spectroscopy," Biotechnol. Bioeng. 100, 82-83 (2008).
[CrossRef]

2007

V. Moreau, M. Bahriz, R. Colombelli, P.-A. Lamoine, Y. DeWilde, and L. R. Wilson, "Direct imaging of a laser mode via midinfrared near-field microscopy," Appl. Phys. Lett. 90, 201114 (2007).
[CrossRef]

M. Sahm, A. Oprea, N. Bârsan, and U. Weimar, "Water and ammonia influence on the conduction mechanisms in polyacrylic acid films," Sens. Actuat. B 127, 204-209 (2007).
[CrossRef]

B. S. Williams, "Terahertz quantum-cascade lasers," Nat. Photon. 1, 517-525 (2007).
[CrossRef]

M. A. Belkin, F. Capasso, A. Belyanin, D. L. Sivco, A. Y. Cho, D. C. Oakley, C. J. Vineis, and G. W. Turner, "Terahertz quantum-cascade-laser source based on intracavity difference-frequency generation," Nat. Photon. 1, 288-292 (2007).
[CrossRef]

M. Lon??ar, B. G. Lee, L. Diehl, M. A. Belkin, F. Capasso, M. Giovannini, J. Faist, and E. Gini, "Design and fabrication of photonic crystal quantum cascade lasers for optofluidics," Opt. Express 15, 4499-4514 (2007).
[CrossRef] [PubMed]

M. A. Belkin, M. Lon??ar, B. G. Lee, C. Pflügl, R. Audet, L. Diehl, F. Capasso, D. Bour, S. Corzine, and G. Höfler, "Intra-cavity absorption spectroscopy with narrow-ridge microfluidic quantum cascade lasers," Opt. Express 15, 11262-11271 (2007).
[CrossRef] [PubMed]

2006

L. Diehl, B. Lee, P. Behroozi, M. Lon??ar, M. Belkin, F. Capasso, T. Aellen, D. Hofstetter, M. Beck, and J. Faist, "Microfluidic tuning of distributed feedback quantum cascade lasers," Opt. Express 14, 11660-11667 (2006).
[CrossRef] [PubMed]

S. Song, S. S. Howard, Z. Liu, A. O. Dirisu, C. F. Gmachl, and C. B. Arnold, "Mode tuning of quantum cascade lasers through optical processing of chalcogenide glass claddings," Appl. Phys. Lett. 89, 041115 (2006).
[CrossRef]

S. Yang, Y. Zhang, Y. Guan, S. Tan, J. Xu, S. Cheng, and X. Zhang, "Water uptake behavior of hydrogen-bonded PVPON-PAA LBL film," Soft Matter 2, 699-704 (2006).
[CrossRef]

2005

A. Oprea and U. Weimar, "High sensitivity polyacrylic acid films for ammonia detection with field effect devices," Sens. Actuat. B 111-112, 572-576 (2005).
[CrossRef]

D. L. Woolard, E. R. Brown, M. Pepper, and M. Kemp, "Terahertz frequency sensing and imaging: a time of reckoning future applications?" Proc. IEEE 93, 1722-1743 (2005).
[CrossRef]

D. Barate, R. Teissier, Y. Wang, and A. N. Baranov, "Short wavelength intersubband emission from InAs/AlSb quantum cascade structures," Appl. Phys. Lett. 87, 051103 (2005).
[CrossRef]

P. Musto, L. Mascia, G. Mensitieri, and G. Ragosta, "Diffusion of water and ammonia through poyimide-silica bicontinuous nanocomposites: interactions and reactions" Polymer 46, 4492-4503 (2005).
[CrossRef]

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

2004

C. Pflügl, W. Schrenk, S. Anders, and G. Strasser, "Spectral dynamics of distributed feedback quantum cascade lasers," Semicond. Sci. Technol. 19, S336-S338 (2004).
[CrossRef]

D. Sarkar and P. Somasundaran, "Conformatinal dynamic of poly(acrylic acid). A study using surface plasmon resonance spectroscopy," Langmuir 20, 4657-4664 (2004).
[CrossRef]

R. P. Green, L. R. Wilson, E. A. Zibik, D. G. Revin, J. W. Cockburn, C. Pflügl, W. Schrenk, G. Strasser, A. B. Krysa, J. S. Roberts, C. M. Tey, and A. G. Cullis, "High-performance distributed feedback quantum cascade lasers grown by metalorganic vapor phase epitaxy," Appl. Phys. Lett. 85, 5529-5531 (2004).
[CrossRef]

2003

R. Colombelli, K. Srinivasan, M. Troccoli, O. Painter, C. F. Gmachl, D. M. Tennant, A. M. Sergent, D. L. Sivco, and A. Y. Cho, F. Capasso, "Quantum Cascade Surface-Emitting Photonic Crystal Laser," Science 302, 1374-1377 (2003).
[CrossRef] [PubMed]

2002

C. Gmachl, D. L. Sivco, R. Colombelli, F. Capasso, and A. Y. Cho, "Ultra-broadband semiconductor laser," Nature 415, 883-887(2002).
[CrossRef] [PubMed]

J. Ulrich, J. Kreuter, W. Schrenk, G. Strasser, and K. Unterrainer, "Long wavelength (15 and 23 µm) GaAs/AlGaAs quantum cascade lasers," Appl. Phys. Lett. 80, 3691-3693 (2002).
[CrossRef]

2001

K. Dioumaev, "Infrared methods for monitoring the protonation state of carboxylic amino acids in the photocycle of bacteriorhodopsin," Biochemistry (Moscow) 66, 1269-1276 (2001).
[CrossRef]

F. Mohammad, M. Z. A. Rahman, and A. Kassim, "An experimental study on diffusion in electrically conducting polymers," Chem. Environ. Res. 10, 41-46 (2001).

1999

D. Hofstetter, J. Faist, M. Beck, and U. Oesterle, "Surface-emitting 10.1 µm quantum-cascade distributed feedback lasers," Appl. Phys. Lett. 75, 3769-3771 (1999).
[CrossRef]

1998

1997

J. Faist, C. Gmachl, F. Capasso, C. Sirtori, C. L. Sivco, J. N. Baillargeon, and A. Y. Cho, "Distributed feedback quantum cascade lasers," Appl. Phys. Lett. 70, 2670-2672(1997).
[CrossRef]

H. Hoffmann, M. L. T. Liveri, and F. P. Cavasino, "Electric birefringence and zero-shear vixcosity studies of the conformational changes of polyacrylic and polymethacrylic acids with pH and concentration," J. Chem. Soc. Faraday Trans. 93, 3161-3165 (1997).
[CrossRef]

1996

M. Sarangan, W. P. Huang, G. P. Li, and T. Makino, "A ridge waveguide DFB laser model including transverse carrier and optical effects," IEEE J. Quantum Electron. 32, 408-416 (1996).
[CrossRef]

1995

M. Saito, T. Gojo, K. Yato, and M. Miyagi, "Optical constants of polymer coatings in the infrared," Infrared Phys. Technol. 36, 1125-1129 (1995).
[CrossRef]

1994

J. Faist, F. Capasso, D. L. Sivco, C. Sitori, A. L. Hutchinson, and A. Y. Cho, "Quantum cascade laser," Science 264, 553-556 (1994).
[CrossRef] [PubMed]

F. L. Buchholz and N. A. Peppas, "Superabsorbent polymers: science and technology" ACS Symp. Ser. 573 (1994).
[CrossRef]

1990

T. Bae, D. A. Scherson, and E. B. Yeager, "Infrared spectroscopic determination of pH changes in diffusionally decoupled thin-layer electrochemical cells," Anal. Chem. 62, 45-49 (1990).
[CrossRef]

1985

J. Buchanan, B. Hird, and T. M. Letcher, "Primary hydration of poly(acrylic acid) sodium salts" Polym. Bull. 16, 493-498 (1985).

Abe, Y.

Aellen, T.

Anders, S.

C. Pflügl, W. Schrenk, S. Anders, and G. Strasser, "Spectral dynamics of distributed feedback quantum cascade lasers," Semicond. Sci. Technol. 19, S336-S338 (2004).
[CrossRef]

Arnold, C. B.

S. Song, S. S. Howard, Z. Liu, A. O. Dirisu, C. F. Gmachl, and C. B. Arnold, "Mode tuning of quantum cascade lasers through optical processing of chalcogenide glass claddings," Appl. Phys. Lett. 89, 041115 (2006).
[CrossRef]

Audet, R.

Austerer, M.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

Bae, T.

T. Bae, D. A. Scherson, and E. B. Yeager, "Infrared spectroscopic determination of pH changes in diffusionally decoupled thin-layer electrochemical cells," Anal. Chem. 62, 45-49 (1990).
[CrossRef]

Bahriz, M.

V. Moreau, M. Bahriz, R. Colombelli, P.-A. Lamoine, Y. DeWilde, and L. R. Wilson, "Direct imaging of a laser mode via midinfrared near-field microscopy," Appl. Phys. Lett. 90, 201114 (2007).
[CrossRef]

Baillargeon, J. N.

J. Faist, C. Gmachl, F. Capasso, C. Sirtori, C. L. Sivco, J. N. Baillargeon, and A. Y. Cho, "Distributed feedback quantum cascade lasers," Appl. Phys. Lett. 70, 2670-2672(1997).
[CrossRef]

Baranov, A. N.

D. Barate, R. Teissier, Y. Wang, and A. N. Baranov, "Short wavelength intersubband emission from InAs/AlSb quantum cascade structures," Appl. Phys. Lett. 87, 051103 (2005).
[CrossRef]

Barate, D.

D. Barate, R. Teissier, Y. Wang, and A. N. Baranov, "Short wavelength intersubband emission from InAs/AlSb quantum cascade structures," Appl. Phys. Lett. 87, 051103 (2005).
[CrossRef]

Beck, M.

Behroozi, P.

Belkin, M.

Belkin, M. A.

Belyanin, A.

M. A. Belkin, F. Capasso, A. Belyanin, D. L. Sivco, A. Y. Cho, D. C. Oakley, C. J. Vineis, and G. W. Turner, "Terahertz quantum-cascade-laser source based on intracavity difference-frequency generation," Nat. Photon. 1, 288-292 (2007).
[CrossRef]

Bour, D.

Brown, E. R.

D. L. Woolard, E. R. Brown, M. Pepper, and M. Kemp, "Terahertz frequency sensing and imaging: a time of reckoning future applications?" Proc. IEEE 93, 1722-1743 (2005).
[CrossRef]

Buchanan, J.

J. Buchanan, B. Hird, and T. M. Letcher, "Primary hydration of poly(acrylic acid) sodium salts" Polym. Bull. 16, 493-498 (1985).

Buchholz, F. L.

F. L. Buchholz and N. A. Peppas, "Superabsorbent polymers: science and technology" ACS Symp. Ser. 573 (1994).
[CrossRef]

Capasso, F.

M. A. Belkin, F. Capasso, A. Belyanin, D. L. Sivco, A. Y. Cho, D. C. Oakley, C. J. Vineis, and G. W. Turner, "Terahertz quantum-cascade-laser source based on intracavity difference-frequency generation," Nat. Photon. 1, 288-292 (2007).
[CrossRef]

M. Lon??ar, B. G. Lee, L. Diehl, M. A. Belkin, F. Capasso, M. Giovannini, J. Faist, and E. Gini, "Design and fabrication of photonic crystal quantum cascade lasers for optofluidics," Opt. Express 15, 4499-4514 (2007).
[CrossRef] [PubMed]

M. A. Belkin, M. Lon??ar, B. G. Lee, C. Pflügl, R. Audet, L. Diehl, F. Capasso, D. Bour, S. Corzine, and G. Höfler, "Intra-cavity absorption spectroscopy with narrow-ridge microfluidic quantum cascade lasers," Opt. Express 15, 11262-11271 (2007).
[CrossRef] [PubMed]

L. Diehl, B. Lee, P. Behroozi, M. Lon??ar, M. Belkin, F. Capasso, T. Aellen, D. Hofstetter, M. Beck, and J. Faist, "Microfluidic tuning of distributed feedback quantum cascade lasers," Opt. Express 14, 11660-11667 (2006).
[CrossRef] [PubMed]

R. Colombelli, K. Srinivasan, M. Troccoli, O. Painter, C. F. Gmachl, D. M. Tennant, A. M. Sergent, D. L. Sivco, and A. Y. Cho, F. Capasso, "Quantum Cascade Surface-Emitting Photonic Crystal Laser," Science 302, 1374-1377 (2003).
[CrossRef] [PubMed]

C. Gmachl, D. L. Sivco, R. Colombelli, F. Capasso, and A. Y. Cho, "Ultra-broadband semiconductor laser," Nature 415, 883-887(2002).
[CrossRef] [PubMed]

J. Faist, C. Gmachl, F. Capasso, C. Sirtori, C. L. Sivco, J. N. Baillargeon, and A. Y. Cho, "Distributed feedback quantum cascade lasers," Appl. Phys. Lett. 70, 2670-2672(1997).
[CrossRef]

J. Faist, F. Capasso, D. L. Sivco, C. Sitori, A. L. Hutchinson, and A. Y. Cho, "Quantum cascade laser," Science 264, 553-556 (1994).
[CrossRef] [PubMed]

Cavasino, F. P.

H. Hoffmann, M. L. T. Liveri, and F. P. Cavasino, "Electric birefringence and zero-shear vixcosity studies of the conformational changes of polyacrylic and polymethacrylic acids with pH and concentration," J. Chem. Soc. Faraday Trans. 93, 3161-3165 (1997).
[CrossRef]

Cheng, S.

S. Yang, Y. Zhang, Y. Guan, S. Tan, J. Xu, S. Cheng, and X. Zhang, "Water uptake behavior of hydrogen-bonded PVPON-PAA LBL film," Soft Matter 2, 699-704 (2006).
[CrossRef]

Cho, A. Y.

M. A. Belkin, F. Capasso, A. Belyanin, D. L. Sivco, A. Y. Cho, D. C. Oakley, C. J. Vineis, and G. W. Turner, "Terahertz quantum-cascade-laser source based on intracavity difference-frequency generation," Nat. Photon. 1, 288-292 (2007).
[CrossRef]

R. Colombelli, K. Srinivasan, M. Troccoli, O. Painter, C. F. Gmachl, D. M. Tennant, A. M. Sergent, D. L. Sivco, and A. Y. Cho, F. Capasso, "Quantum Cascade Surface-Emitting Photonic Crystal Laser," Science 302, 1374-1377 (2003).
[CrossRef] [PubMed]

C. Gmachl, D. L. Sivco, R. Colombelli, F. Capasso, and A. Y. Cho, "Ultra-broadband semiconductor laser," Nature 415, 883-887(2002).
[CrossRef] [PubMed]

J. Faist, C. Gmachl, F. Capasso, C. Sirtori, C. L. Sivco, J. N. Baillargeon, and A. Y. Cho, "Distributed feedback quantum cascade lasers," Appl. Phys. Lett. 70, 2670-2672(1997).
[CrossRef]

J. Faist, F. Capasso, D. L. Sivco, C. Sitori, A. L. Hutchinson, and A. Y. Cho, "Quantum cascade laser," Science 264, 553-556 (1994).
[CrossRef] [PubMed]

Cockburn, J. W.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

R. P. Green, L. R. Wilson, E. A. Zibik, D. G. Revin, J. W. Cockburn, C. Pflügl, W. Schrenk, G. Strasser, A. B. Krysa, J. S. Roberts, C. M. Tey, and A. G. Cullis, "High-performance distributed feedback quantum cascade lasers grown by metalorganic vapor phase epitaxy," Appl. Phys. Lett. 85, 5529-5531 (2004).
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V. Moreau, M. Bahriz, R. Colombelli, P.-A. Lamoine, Y. DeWilde, and L. R. Wilson, "Direct imaging of a laser mode via midinfrared near-field microscopy," Appl. Phys. Lett. 90, 201114 (2007).
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R. Colombelli, K. Srinivasan, M. Troccoli, O. Painter, C. F. Gmachl, D. M. Tennant, A. M. Sergent, D. L. Sivco, and A. Y. Cho, F. Capasso, "Quantum Cascade Surface-Emitting Photonic Crystal Laser," Science 302, 1374-1377 (2003).
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C. Gmachl, D. L. Sivco, R. Colombelli, F. Capasso, and A. Y. Cho, "Ultra-broadband semiconductor laser," Nature 415, 883-887(2002).
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Corzine, S.

Cullis, A. G.

R. P. Green, L. R. Wilson, E. A. Zibik, D. G. Revin, J. W. Cockburn, C. Pflügl, W. Schrenk, G. Strasser, A. B. Krysa, J. S. Roberts, C. M. Tey, and A. G. Cullis, "High-performance distributed feedback quantum cascade lasers grown by metalorganic vapor phase epitaxy," Appl. Phys. Lett. 85, 5529-5531 (2004).
[CrossRef]

DeWilde, Y.

V. Moreau, M. Bahriz, R. Colombelli, P.-A. Lamoine, Y. DeWilde, and L. R. Wilson, "Direct imaging of a laser mode via midinfrared near-field microscopy," Appl. Phys. Lett. 90, 201114 (2007).
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Diehl, L.

Dioumaev, K.

K. Dioumaev, "Infrared methods for monitoring the protonation state of carboxylic amino acids in the photocycle of bacteriorhodopsin," Biochemistry (Moscow) 66, 1269-1276 (2001).
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S. Song, S. S. Howard, Z. Liu, A. O. Dirisu, C. F. Gmachl, and C. B. Arnold, "Mode tuning of quantum cascade lasers through optical processing of chalcogenide glass claddings," Appl. Phys. Lett. 89, 041115 (2006).
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Faist, J.

M. Lon??ar, B. G. Lee, L. Diehl, M. A. Belkin, F. Capasso, M. Giovannini, J. Faist, and E. Gini, "Design and fabrication of photonic crystal quantum cascade lasers for optofluidics," Opt. Express 15, 4499-4514 (2007).
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L. Diehl, B. Lee, P. Behroozi, M. Lon??ar, M. Belkin, F. Capasso, T. Aellen, D. Hofstetter, M. Beck, and J. Faist, "Microfluidic tuning of distributed feedback quantum cascade lasers," Opt. Express 14, 11660-11667 (2006).
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D. Hofstetter, J. Faist, M. Beck, and U. Oesterle, "Surface-emitting 10.1 µm quantum-cascade distributed feedback lasers," Appl. Phys. Lett. 75, 3769-3771 (1999).
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J. Faist, C. Gmachl, F. Capasso, C. Sirtori, C. L. Sivco, J. N. Baillargeon, and A. Y. Cho, "Distributed feedback quantum cascade lasers," Appl. Phys. Lett. 70, 2670-2672(1997).
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J. Faist, F. Capasso, D. L. Sivco, C. Sitori, A. L. Hutchinson, and A. Y. Cho, "Quantum cascade laser," Science 264, 553-556 (1994).
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Gini, E.

Giovannini, M.

Gmachl, C.

C. Gmachl, D. L. Sivco, R. Colombelli, F. Capasso, and A. Y. Cho, "Ultra-broadband semiconductor laser," Nature 415, 883-887(2002).
[CrossRef] [PubMed]

J. Faist, C. Gmachl, F. Capasso, C. Sirtori, C. L. Sivco, J. N. Baillargeon, and A. Y. Cho, "Distributed feedback quantum cascade lasers," Appl. Phys. Lett. 70, 2670-2672(1997).
[CrossRef]

Gmachl, C. F.

S. Song, S. S. Howard, Z. Liu, A. O. Dirisu, C. F. Gmachl, and C. B. Arnold, "Mode tuning of quantum cascade lasers through optical processing of chalcogenide glass claddings," Appl. Phys. Lett. 89, 041115 (2006).
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R. Colombelli, K. Srinivasan, M. Troccoli, O. Painter, C. F. Gmachl, D. M. Tennant, A. M. Sergent, D. L. Sivco, and A. Y. Cho, F. Capasso, "Quantum Cascade Surface-Emitting Photonic Crystal Laser," Science 302, 1374-1377 (2003).
[CrossRef] [PubMed]

Golka, S.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

Green, R. P.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

R. P. Green, L. R. Wilson, E. A. Zibik, D. G. Revin, J. W. Cockburn, C. Pflügl, W. Schrenk, G. Strasser, A. B. Krysa, J. S. Roberts, C. M. Tey, and A. G. Cullis, "High-performance distributed feedback quantum cascade lasers grown by metalorganic vapor phase epitaxy," Appl. Phys. Lett. 85, 5529-5531 (2004).
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Guan, Y.

S. Yang, Y. Zhang, Y. Guan, S. Tan, J. Xu, S. Cheng, and X. Zhang, "Water uptake behavior of hydrogen-bonded PVPON-PAA LBL film," Soft Matter 2, 699-704 (2006).
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H. Hoffmann, M. L. T. Liveri, and F. P. Cavasino, "Electric birefringence and zero-shear vixcosity studies of the conformational changes of polyacrylic and polymethacrylic acids with pH and concentration," J. Chem. Soc. Faraday Trans. 93, 3161-3165 (1997).
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Höfler, G.

Hofstetter, D.

Howard, S. S.

S. Song, S. S. Howard, Z. Liu, A. O. Dirisu, C. F. Gmachl, and C. B. Arnold, "Mode tuning of quantum cascade lasers through optical processing of chalcogenide glass claddings," Appl. Phys. Lett. 89, 041115 (2006).
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M. Sarangan, W. P. Huang, G. P. Li, and T. Makino, "A ridge waveguide DFB laser model including transverse carrier and optical effects," IEEE J. Quantum Electron. 32, 408-416 (1996).
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Hutchinson, A. L.

J. Faist, F. Capasso, D. L. Sivco, C. Sitori, A. L. Hutchinson, and A. Y. Cho, "Quantum cascade laser," Science 264, 553-556 (1994).
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F. Mohammad, M. Z. A. Rahman, and A. Kassim, "An experimental study on diffusion in electrically conducting polymers," Chem. Environ. Res. 10, 41-46 (2001).

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D. L. Woolard, E. R. Brown, M. Pepper, and M. Kemp, "Terahertz frequency sensing and imaging: a time of reckoning future applications?" Proc. IEEE 93, 1722-1743 (2005).
[CrossRef]

Kreuter, J.

J. Ulrich, J. Kreuter, W. Schrenk, G. Strasser, and K. Unterrainer, "Long wavelength (15 and 23 µm) GaAs/AlGaAs quantum cascade lasers," Appl. Phys. Lett. 80, 3691-3693 (2002).
[CrossRef]

Krysa, A. B.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

R. P. Green, L. R. Wilson, E. A. Zibik, D. G. Revin, J. W. Cockburn, C. Pflügl, W. Schrenk, G. Strasser, A. B. Krysa, J. S. Roberts, C. M. Tey, and A. G. Cullis, "High-performance distributed feedback quantum cascade lasers grown by metalorganic vapor phase epitaxy," Appl. Phys. Lett. 85, 5529-5531 (2004).
[CrossRef]

Lamoine, P.-A.

V. Moreau, M. Bahriz, R. Colombelli, P.-A. Lamoine, Y. DeWilde, and L. R. Wilson, "Direct imaging of a laser mode via midinfrared near-field microscopy," Appl. Phys. Lett. 90, 201114 (2007).
[CrossRef]

Lee, B.

Lee, B. G.

Letcher, T. M.

J. Buchanan, B. Hird, and T. M. Letcher, "Primary hydration of poly(acrylic acid) sodium salts" Polym. Bull. 16, 493-498 (1985).

Li, G. P.

M. Sarangan, W. P. Huang, G. P. Li, and T. Makino, "A ridge waveguide DFB laser model including transverse carrier and optical effects," IEEE J. Quantum Electron. 32, 408-416 (1996).
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Liu, Z.

S. Song, S. S. Howard, Z. Liu, A. O. Dirisu, C. F. Gmachl, and C. B. Arnold, "Mode tuning of quantum cascade lasers through optical processing of chalcogenide glass claddings," Appl. Phys. Lett. 89, 041115 (2006).
[CrossRef]

Liveri, M. L. T.

H. Hoffmann, M. L. T. Liveri, and F. P. Cavasino, "Electric birefringence and zero-shear vixcosity studies of the conformational changes of polyacrylic and polymethacrylic acids with pH and concentration," J. Chem. Soc. Faraday Trans. 93, 3161-3165 (1997).
[CrossRef]

Lon??ar, M.

Makino, T.

M. Sarangan, W. P. Huang, G. P. Li, and T. Makino, "A ridge waveguide DFB laser model including transverse carrier and optical effects," IEEE J. Quantum Electron. 32, 408-416 (1996).
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P. Musto, L. Mascia, G. Mensitieri, and G. Ragosta, "Diffusion of water and ammonia through poyimide-silica bicontinuous nanocomposites: interactions and reactions" Polymer 46, 4492-4503 (2005).
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Mensitieri, G.

P. Musto, L. Mascia, G. Mensitieri, and G. Ragosta, "Diffusion of water and ammonia through poyimide-silica bicontinuous nanocomposites: interactions and reactions" Polymer 46, 4492-4503 (2005).
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Miyagi, M.

Mohammad, F.

F. Mohammad, M. Z. A. Rahman, and A. Kassim, "An experimental study on diffusion in electrically conducting polymers," Chem. Environ. Res. 10, 41-46 (2001).

Moreau, V.

V. Moreau, M. Bahriz, R. Colombelli, P.-A. Lamoine, Y. DeWilde, and L. R. Wilson, "Direct imaging of a laser mode via midinfrared near-field microscopy," Appl. Phys. Lett. 90, 201114 (2007).
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P. Musto, L. Mascia, G. Mensitieri, and G. Ragosta, "Diffusion of water and ammonia through poyimide-silica bicontinuous nanocomposites: interactions and reactions" Polymer 46, 4492-4503 (2005).
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M. A. Belkin, F. Capasso, A. Belyanin, D. L. Sivco, A. Y. Cho, D. C. Oakley, C. J. Vineis, and G. W. Turner, "Terahertz quantum-cascade-laser source based on intracavity difference-frequency generation," Nat. Photon. 1, 288-292 (2007).
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Oesterle, U.

D. Hofstetter, J. Faist, M. Beck, and U. Oesterle, "Surface-emitting 10.1 µm quantum-cascade distributed feedback lasers," Appl. Phys. Lett. 75, 3769-3771 (1999).
[CrossRef]

Painter, O.

R. Colombelli, K. Srinivasan, M. Troccoli, O. Painter, C. F. Gmachl, D. M. Tennant, A. M. Sergent, D. L. Sivco, and A. Y. Cho, F. Capasso, "Quantum Cascade Surface-Emitting Photonic Crystal Laser," Science 302, 1374-1377 (2003).
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F. L. Buchholz and N. A. Peppas, "Superabsorbent polymers: science and technology" ACS Symp. Ser. 573 (1994).
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D. L. Woolard, E. R. Brown, M. Pepper, and M. Kemp, "Terahertz frequency sensing and imaging: a time of reckoning future applications?" Proc. IEEE 93, 1722-1743 (2005).
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M. A. Belkin, M. Lon??ar, B. G. Lee, C. Pflügl, R. Audet, L. Diehl, F. Capasso, D. Bour, S. Corzine, and G. Höfler, "Intra-cavity absorption spectroscopy with narrow-ridge microfluidic quantum cascade lasers," Opt. Express 15, 11262-11271 (2007).
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C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

R. P. Green, L. R. Wilson, E. A. Zibik, D. G. Revin, J. W. Cockburn, C. Pflügl, W. Schrenk, G. Strasser, A. B. Krysa, J. S. Roberts, C. M. Tey, and A. G. Cullis, "High-performance distributed feedback quantum cascade lasers grown by metalorganic vapor phase epitaxy," Appl. Phys. Lett. 85, 5529-5531 (2004).
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C. Pflügl, W. Schrenk, S. Anders, and G. Strasser, "Spectral dynamics of distributed feedback quantum cascade lasers," Semicond. Sci. Technol. 19, S336-S338 (2004).
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Ragosta, G.

P. Musto, L. Mascia, G. Mensitieri, and G. Ragosta, "Diffusion of water and ammonia through poyimide-silica bicontinuous nanocomposites: interactions and reactions" Polymer 46, 4492-4503 (2005).
[CrossRef]

Rahman, M. Z. A.

F. Mohammad, M. Z. A. Rahman, and A. Kassim, "An experimental study on diffusion in electrically conducting polymers," Chem. Environ. Res. 10, 41-46 (2001).

Revin, D. G.

R. P. Green, L. R. Wilson, E. A. Zibik, D. G. Revin, J. W. Cockburn, C. Pflügl, W. Schrenk, G. Strasser, A. B. Krysa, J. S. Roberts, C. M. Tey, and A. G. Cullis, "High-performance distributed feedback quantum cascade lasers grown by metalorganic vapor phase epitaxy," Appl. Phys. Lett. 85, 5529-5531 (2004).
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Roberts, J. S.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
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R. P. Green, L. R. Wilson, E. A. Zibik, D. G. Revin, J. W. Cockburn, C. Pflügl, W. Schrenk, G. Strasser, A. B. Krysa, J. S. Roberts, C. M. Tey, and A. G. Cullis, "High-performance distributed feedback quantum cascade lasers grown by metalorganic vapor phase epitaxy," Appl. Phys. Lett. 85, 5529-5531 (2004).
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M. Sarangan, W. P. Huang, G. P. Li, and T. Makino, "A ridge waveguide DFB laser model including transverse carrier and optical effects," IEEE J. Quantum Electron. 32, 408-416 (1996).
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D. Sarkar and P. Somasundaran, "Conformatinal dynamic of poly(acrylic acid). A study using surface plasmon resonance spectroscopy," Langmuir 20, 4657-4664 (2004).
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Schrenk, W.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

R. P. Green, L. R. Wilson, E. A. Zibik, D. G. Revin, J. W. Cockburn, C. Pflügl, W. Schrenk, G. Strasser, A. B. Krysa, J. S. Roberts, C. M. Tey, and A. G. Cullis, "High-performance distributed feedback quantum cascade lasers grown by metalorganic vapor phase epitaxy," Appl. Phys. Lett. 85, 5529-5531 (2004).
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C. Pflügl, W. Schrenk, S. Anders, and G. Strasser, "Spectral dynamics of distributed feedback quantum cascade lasers," Semicond. Sci. Technol. 19, S336-S338 (2004).
[CrossRef]

J. Ulrich, J. Kreuter, W. Schrenk, G. Strasser, and K. Unterrainer, "Long wavelength (15 and 23 µm) GaAs/AlGaAs quantum cascade lasers," Appl. Phys. Lett. 80, 3691-3693 (2002).
[CrossRef]

Sergent, A. M.

R. Colombelli, K. Srinivasan, M. Troccoli, O. Painter, C. F. Gmachl, D. M. Tennant, A. M. Sergent, D. L. Sivco, and A. Y. Cho, F. Capasso, "Quantum Cascade Surface-Emitting Photonic Crystal Laser," Science 302, 1374-1377 (2003).
[CrossRef] [PubMed]

Sirtori, C.

J. Faist, C. Gmachl, F. Capasso, C. Sirtori, C. L. Sivco, J. N. Baillargeon, and A. Y. Cho, "Distributed feedback quantum cascade lasers," Appl. Phys. Lett. 70, 2670-2672(1997).
[CrossRef]

Sitori, C.

J. Faist, F. Capasso, D. L. Sivco, C. Sitori, A. L. Hutchinson, and A. Y. Cho, "Quantum cascade laser," Science 264, 553-556 (1994).
[CrossRef] [PubMed]

Sivco, C. L.

J. Faist, C. Gmachl, F. Capasso, C. Sirtori, C. L. Sivco, J. N. Baillargeon, and A. Y. Cho, "Distributed feedback quantum cascade lasers," Appl. Phys. Lett. 70, 2670-2672(1997).
[CrossRef]

Sivco, D. L.

M. A. Belkin, F. Capasso, A. Belyanin, D. L. Sivco, A. Y. Cho, D. C. Oakley, C. J. Vineis, and G. W. Turner, "Terahertz quantum-cascade-laser source based on intracavity difference-frequency generation," Nat. Photon. 1, 288-292 (2007).
[CrossRef]

R. Colombelli, K. Srinivasan, M. Troccoli, O. Painter, C. F. Gmachl, D. M. Tennant, A. M. Sergent, D. L. Sivco, and A. Y. Cho, F. Capasso, "Quantum Cascade Surface-Emitting Photonic Crystal Laser," Science 302, 1374-1377 (2003).
[CrossRef] [PubMed]

C. Gmachl, D. L. Sivco, R. Colombelli, F. Capasso, and A. Y. Cho, "Ultra-broadband semiconductor laser," Nature 415, 883-887(2002).
[CrossRef] [PubMed]

J. Faist, F. Capasso, D. L. Sivco, C. Sitori, A. L. Hutchinson, and A. Y. Cho, "Quantum cascade laser," Science 264, 553-556 (1994).
[CrossRef] [PubMed]

Somasundaran, P.

D. Sarkar and P. Somasundaran, "Conformatinal dynamic of poly(acrylic acid). A study using surface plasmon resonance spectroscopy," Langmuir 20, 4657-4664 (2004).
[CrossRef]

Song, S.

S. Song, S. S. Howard, Z. Liu, A. O. Dirisu, C. F. Gmachl, and C. B. Arnold, "Mode tuning of quantum cascade lasers through optical processing of chalcogenide glass claddings," Appl. Phys. Lett. 89, 041115 (2006).
[CrossRef]

Srinivasan, K.

R. Colombelli, K. Srinivasan, M. Troccoli, O. Painter, C. F. Gmachl, D. M. Tennant, A. M. Sergent, D. L. Sivco, and A. Y. Cho, F. Capasso, "Quantum Cascade Surface-Emitting Photonic Crystal Laser," Science 302, 1374-1377 (2003).
[CrossRef] [PubMed]

Strasser, G.

C. Pflügl, M. Austerer, W. Schrenk, S. Golka, G. Strasser, R. P. Green, L. R. Wilson, J. W. Cockburn, A. B. Krysa, and J. S. Roberts, "Single-mode surface-emitting quantum-cascade lasers," Appl. Phys. Lett. 86, 211102 (2005).
[CrossRef]

C. Pflügl, W. Schrenk, S. Anders, and G. Strasser, "Spectral dynamics of distributed feedback quantum cascade lasers," Semicond. Sci. Technol. 19, S336-S338 (2004).
[CrossRef]

R. P. Green, L. R. Wilson, E. A. Zibik, D. G. Revin, J. W. Cockburn, C. Pflügl, W. Schrenk, G. Strasser, A. B. Krysa, J. S. Roberts, C. M. Tey, and A. G. Cullis, "High-performance distributed feedback quantum cascade lasers grown by metalorganic vapor phase epitaxy," Appl. Phys. Lett. 85, 5529-5531 (2004).
[CrossRef]

J. Ulrich, J. Kreuter, W. Schrenk, G. Strasser, and K. Unterrainer, "Long wavelength (15 and 23 µm) GaAs/AlGaAs quantum cascade lasers," Appl. Phys. Lett. 80, 3691-3693 (2002).
[CrossRef]

Tan, S.

S. Yang, Y. Zhang, Y. Guan, S. Tan, J. Xu, S. Cheng, and X. Zhang, "Water uptake behavior of hydrogen-bonded PVPON-PAA LBL film," Soft Matter 2, 699-704 (2006).
[CrossRef]

Teissier, R.

D. Barate, R. Teissier, Y. Wang, and A. N. Baranov, "Short wavelength intersubband emission from InAs/AlSb quantum cascade structures," Appl. Phys. Lett. 87, 051103 (2005).
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Tennant, D. M.

R. Colombelli, K. Srinivasan, M. Troccoli, O. Painter, C. F. Gmachl, D. M. Tennant, A. M. Sergent, D. L. Sivco, and A. Y. Cho, F. Capasso, "Quantum Cascade Surface-Emitting Photonic Crystal Laser," Science 302, 1374-1377 (2003).
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Figures (7)

Fig. 1.
Fig. 1.

Basic design of the PAA-coated QCLs

Fig. 2.
Fig. 2.

(a) Absorbance FTIR spectra of PAA in its acid (red, dashed curve) and potassium salt state (blue, solid curve) measured in transmission on a 2 µm thick film of PAA on silicon. (b) Close-up of the absorbance spectrum in the range between 1200 and 1400 cm-1. The gray rectangle marks the emission wavenumber range of the QCLs.

Fig. 3.
Fig. 3.

Emission spectra of QCLs with different ridge width, ranging from 28 to 58 µm. Dotted black lines represent the native QCLs, solid blue lines represents the PAA/potassium salt coated QCLs, and dashed red lines represent the PAA in its acid-state. All lasers are 2 mm long and are operated at room temperature. The thickness of the PAA coating is 500 nm.

Fig. 4.
Fig. 4.

Time-resolved transmission FTIR-characterization of the pH-switching behavior of a 2 µm film of PAA at 1725 cm-1 and 1550 cm-1. (a) Change of the transmissivity of the salt-state PAA during a 20 s exposure to HCl vapours. (b) Change of the transmissivity of the acid-state PAA during a 20 s exposure to NH3 vapors. (c) Repeated switching between acid- and salt-state PAA every 15s. The related spectra were recorded every 1.5s with a spectral resolution of 2 cm-1 at room temperature.

Fig. 5.
Fig. 5.

Time-resolved emission-characterization of the pH-switching behavior of the 38 µm wide QCL. (a) Change in the emission spectrum of the acid-state laser upon exposure to ammonia vapors. Spectral resolution is 0.5 cm-1. Flushing of the laser with ammonia vapors was initiated after 4 s. (b) Change in the emission spectrum of the ammonium salt-state PAA due to the effusion of ammonia from the polymer. (c) Repeated switching between acid- and salt-state PAA by exposure to ammonia vapor (switch to even numbers) and effusion of ammonia from the polymer or exposure to HCl vapors (switch to odd numbers). Numbers represent the centre of a gaussian fit to the emission spectra peak. All measurements were performed at room temperature.

Fig. 6.
Fig. 6.

IV-characteristics and power output of the 38 µm wide QCL for different modifications. The dotted black curves represent the IV and the peak power for the native QCL, the solid blue lines represent the same laser after PAA/potassium salt coating, and the dashed red line represents the same laser after a 15 s exposure to HCl vapors. All measurements were performed at room temperature.

Fig. 7.
Fig. 7.

(a) and (b) show the refractive index line ups together with calculated waveguide modes for the native laser and for a laser with a 500 nm layer of polymer on top, respectively. The effective refractive index as well as the confinement to the active region stay almost constant whereas losses increase by 20%. This can also be seen in (c) presenting the influence of the polymer thickness on the confinement factor Γ (dashed line) and the waveguide losses αw (solid line).

Equations (3)

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λ = 2 Λ n eff
ε = A d · c
α = A d

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