Abstract

We present results on a 404 nm laser system based on second harmonic generation in a new compact external cavity configuration. We obtain a stable 318 mW cw diffraction limited output from the system with a mode-matched pump power of 630 mW. We observe up to 620 mW SHG, when the cavity is operating in scanning mode. The pump source is an external cavity grating feedback tapered diode laser operating at 808 nm. We find that thermal effects in the nonlinear crystal severely limit the efficiency of the setup with high input powers.

©2008 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
High-power 390-nm laser source based on efficient frequency doubling of a tapered diode laser in an external resonant cavity

J. D. Bhawalkar, Y. Mao, H. Po, A. K. Goyal, P. Gavrilovic, Y. Conturie, and S. Singh
Opt. Lett. 24(12) 823-825 (1999)

Tunable high-power narrow-spectrum external-cavity diode laser at 675 nm as a pump source for UV generation

Mingjun Chi, Ole Bjarlin Jensen, Götz Erbert, Bernd Sumpf, and Paul Michael Petersen
Appl. Opt. 50(1) 90-94 (2011)

Tunable high-power narrow-linewidth semiconductor laser based on an external-cavity tapered amplifier

Mingjun Chi, Ole Bjarlin Jensen, Jesper Holm, Christian Pedersen, Peter Eskil Andersen, Götz Erbert, Bernd Sumpf, and Paul Michael Petersen
Opt. Express 13(26) 10589-10596 (2005)

References

  • View by:
  • |
  • |
  • |

  1. M. Chi, O. B. Jensen, J. Holm, C. Pedersen, P. E. Andersen, G. Erbert, B. Sumpf, and P. M. Petersen, “Tunable high-power narrow-linewidth semiconductor laser based on an external-cavity tapered amplifier,” Opt. Express 13, 10589–10596 (2005).
    [Crossref] [PubMed]
  2. H. Wenzel, B. Sumpf, and G. Erbert, “High-brightness diode lasers,” C. R. Physique 4, 649–661 (2003).
    [Crossref]
  3. F. Torabi-Goudarzi and E. Riis, “Efficient cw high-power frequency doubling in periodically poled KTP,” Opt. Commun. 227, 389–403 (2003).
    [Crossref]
  4. R. Le. Targat, J.-J. Zondy, and P. Lemonde, “75%-Efficiency blue generation from an intracavity PPKTP frequency doubler,” Opt. Commun. 247, 471–481 (2005).
    [Crossref]
  5. F. Villa, A. Chiummo, E. Giacobino, and A. Bramati, “High-efficiency blue-light generation with a ring cavity with periodically poled KTP,” J. Opt. Soc. Am. B 24, 576–580 (2007).
    [Crossref]
  6. J. D. Bhawalkar, Y. Mao, H. Po, A. K. Goyal, P. Gavrilovic, Y. Conturie, and S. Singh, “High-power 390-nm laser source based on efficient frequency doubling of a tapered diode laser in an external resonant cavity,” Opt. Lett. 24, 823–825 (1999).
    [Crossref]
  7. B. Beier, D. Woll, M. Scheidt, K.-J. Boller, and R. Wallenstein, “Second harmonic generation of the output of an AlGaAs diode oscillator amplifier system in critically phase matched LiB3O5 and β-BaB2O4,” Appl. Phys. Lett. 71, 315–317 (1997).
    [Crossref]
  8. A. Knauer, G. Erbert, R. Staske, B. Sumpf, H. Wenzel, and M. Weyers, “High-power 808-nm lasers with a super-large optical cavity,” Semicond. Sci. Technol. 20, 621–624 (2005).
    [Crossref]
  9. B. Boulanger, I. Rousseau, J. P. Fève, M. Maglione, B. Ménaert, and G. Marnier, “Optical Studies of Laser-Induced Gray-Tracking in KTP,” IEEE J. Quantum Electron. 35, 281–286 (1999).
    [Crossref]
  10. T. Freegarde, J. Coutts, J. Walz, D. Leibfried, and T. W. Hänsch, “General analysis of type I second-harmonic generation with elliptical Gaussian beams,” J. Opt. Soc. Am. B 14, 2010–2016 (1997).
    [Crossref]
  11. G. D. Boyd and D. A. Kleinman, “Parametric Interaction of Focused Gaussian Light Beams,” J. Appl. Phys. 39, 3597–3639 (1968).
    [Crossref]
  12. A. E. Siegman, Lasers (University Science, Mill Valley, Calif., 1986).
  13. G. Hansson, F. Laurell, and S Wang, “Transmission measurements in KTP and isomorphic compounds,” Appl. Opt. 39, 5058–5069 (2000).
    [Crossref]
  14. A. Ashkin, G. D. Boyd, and J. M. Dziedzic, “Resonant optical second harmonic generation and mixing,” IEEE J. Quantum Electron. 2, 109–124 (1966).
    [Crossref]
  15. E. S. Polzik and H. J. Kimble, “Frequency doubling with KNbO3 in an external cavity,” Opt. Lett. 16, 1400–1402 (1991).
    [Crossref] [PubMed]
  16. M.M. Fejer, G. A. Magel, D. H. Jundt, and R. L. Byer,” Quasi-Phase-Matched Second Harmonic Generation: Tuning and Tolerances,” IEEE J. Quantum Electron. 28, 2631–2654 (1992).
    [Crossref]
  17. W. P. Risk et al, Compact Blue-Green lasers (Cambridge Univercity Press, Cambridge, UK, 2003).
  18. John D. Bierlein and Herman Vanherzeele, “Potassium titanyl phosphate: properties and new applications,” J. Opt. Soc. Am. B 6, 622–633 (1989).
    [Crossref]
  19. W. Wiechmann, S. Kubota, T. Fukui, and H. Masuda, “Refractive-index temperature derivatives of potassium titanyl phosphate,” Opt. Lett. 18, 1208–1210 (1993).
    [Crossref] [PubMed]
  20. T. W. Hänsch and B. Couillaud, “Laser frequency stabilization by polarization spectroscopy of a reflecting reference cavity,” Opt. Commun. 35, 441–444 (1980).
    [Crossref]
  21. P. Dubé, L.-S. Ma, J. Ye, P. Jungner, and J. L. Hall, “Thermally induced self-locking of an optical cavity by overtone absorption in acetylene gas,” J. Opt. Soc. Am. B 13, 2041–2054 (1996).
    [Crossref]
  22. A. Douillet, J. -J. Zondy, A. Yelisseyev, S. Lobanov, and L. Isaenko, “Stability and frequency tuning of thermally loaded continuous-wave AgGaS2 optical parametric oscillators,” J. Opt. Soc. Am. B 16, 1481–1498 (1999).
    [Crossref]

2007 (1)

2005 (3)

M. Chi, O. B. Jensen, J. Holm, C. Pedersen, P. E. Andersen, G. Erbert, B. Sumpf, and P. M. Petersen, “Tunable high-power narrow-linewidth semiconductor laser based on an external-cavity tapered amplifier,” Opt. Express 13, 10589–10596 (2005).
[Crossref] [PubMed]

R. Le. Targat, J.-J. Zondy, and P. Lemonde, “75%-Efficiency blue generation from an intracavity PPKTP frequency doubler,” Opt. Commun. 247, 471–481 (2005).
[Crossref]

A. Knauer, G. Erbert, R. Staske, B. Sumpf, H. Wenzel, and M. Weyers, “High-power 808-nm lasers with a super-large optical cavity,” Semicond. Sci. Technol. 20, 621–624 (2005).
[Crossref]

2003 (2)

H. Wenzel, B. Sumpf, and G. Erbert, “High-brightness diode lasers,” C. R. Physique 4, 649–661 (2003).
[Crossref]

F. Torabi-Goudarzi and E. Riis, “Efficient cw high-power frequency doubling in periodically poled KTP,” Opt. Commun. 227, 389–403 (2003).
[Crossref]

2000 (1)

1999 (3)

1997 (2)

B. Beier, D. Woll, M. Scheidt, K.-J. Boller, and R. Wallenstein, “Second harmonic generation of the output of an AlGaAs diode oscillator amplifier system in critically phase matched LiB3O5 and β-BaB2O4,” Appl. Phys. Lett. 71, 315–317 (1997).
[Crossref]

T. Freegarde, J. Coutts, J. Walz, D. Leibfried, and T. W. Hänsch, “General analysis of type I second-harmonic generation with elliptical Gaussian beams,” J. Opt. Soc. Am. B 14, 2010–2016 (1997).
[Crossref]

1996 (1)

1993 (1)

1992 (1)

M.M. Fejer, G. A. Magel, D. H. Jundt, and R. L. Byer,” Quasi-Phase-Matched Second Harmonic Generation: Tuning and Tolerances,” IEEE J. Quantum Electron. 28, 2631–2654 (1992).
[Crossref]

1991 (1)

1989 (1)

1980 (1)

T. W. Hänsch and B. Couillaud, “Laser frequency stabilization by polarization spectroscopy of a reflecting reference cavity,” Opt. Commun. 35, 441–444 (1980).
[Crossref]

1968 (1)

G. D. Boyd and D. A. Kleinman, “Parametric Interaction of Focused Gaussian Light Beams,” J. Appl. Phys. 39, 3597–3639 (1968).
[Crossref]

1966 (1)

A. Ashkin, G. D. Boyd, and J. M. Dziedzic, “Resonant optical second harmonic generation and mixing,” IEEE J. Quantum Electron. 2, 109–124 (1966).
[Crossref]

Andersen, P. E.

Ashkin, A.

A. Ashkin, G. D. Boyd, and J. M. Dziedzic, “Resonant optical second harmonic generation and mixing,” IEEE J. Quantum Electron. 2, 109–124 (1966).
[Crossref]

Beier, B.

B. Beier, D. Woll, M. Scheidt, K.-J. Boller, and R. Wallenstein, “Second harmonic generation of the output of an AlGaAs diode oscillator amplifier system in critically phase matched LiB3O5 and β-BaB2O4,” Appl. Phys. Lett. 71, 315–317 (1997).
[Crossref]

Bhawalkar, J. D.

Bierlein, John D.

Boller, K.-J.

B. Beier, D. Woll, M. Scheidt, K.-J. Boller, and R. Wallenstein, “Second harmonic generation of the output of an AlGaAs diode oscillator amplifier system in critically phase matched LiB3O5 and β-BaB2O4,” Appl. Phys. Lett. 71, 315–317 (1997).
[Crossref]

Boulanger, B.

B. Boulanger, I. Rousseau, J. P. Fève, M. Maglione, B. Ménaert, and G. Marnier, “Optical Studies of Laser-Induced Gray-Tracking in KTP,” IEEE J. Quantum Electron. 35, 281–286 (1999).
[Crossref]

Boyd, G. D.

G. D. Boyd and D. A. Kleinman, “Parametric Interaction of Focused Gaussian Light Beams,” J. Appl. Phys. 39, 3597–3639 (1968).
[Crossref]

A. Ashkin, G. D. Boyd, and J. M. Dziedzic, “Resonant optical second harmonic generation and mixing,” IEEE J. Quantum Electron. 2, 109–124 (1966).
[Crossref]

Bramati, A.

Byer, R. L.

M.M. Fejer, G. A. Magel, D. H. Jundt, and R. L. Byer,” Quasi-Phase-Matched Second Harmonic Generation: Tuning and Tolerances,” IEEE J. Quantum Electron. 28, 2631–2654 (1992).
[Crossref]

Chi, M.

Chiummo, A.

Conturie, Y.

Couillaud, B.

T. W. Hänsch and B. Couillaud, “Laser frequency stabilization by polarization spectroscopy of a reflecting reference cavity,” Opt. Commun. 35, 441–444 (1980).
[Crossref]

Coutts, J.

Douillet, A.

Dubé, P.

Dziedzic, J. M.

A. Ashkin, G. D. Boyd, and J. M. Dziedzic, “Resonant optical second harmonic generation and mixing,” IEEE J. Quantum Electron. 2, 109–124 (1966).
[Crossref]

Erbert, G.

A. Knauer, G. Erbert, R. Staske, B. Sumpf, H. Wenzel, and M. Weyers, “High-power 808-nm lasers with a super-large optical cavity,” Semicond. Sci. Technol. 20, 621–624 (2005).
[Crossref]

M. Chi, O. B. Jensen, J. Holm, C. Pedersen, P. E. Andersen, G. Erbert, B. Sumpf, and P. M. Petersen, “Tunable high-power narrow-linewidth semiconductor laser based on an external-cavity tapered amplifier,” Opt. Express 13, 10589–10596 (2005).
[Crossref] [PubMed]

H. Wenzel, B. Sumpf, and G. Erbert, “High-brightness diode lasers,” C. R. Physique 4, 649–661 (2003).
[Crossref]

Fejer, M.M.

M.M. Fejer, G. A. Magel, D. H. Jundt, and R. L. Byer,” Quasi-Phase-Matched Second Harmonic Generation: Tuning and Tolerances,” IEEE J. Quantum Electron. 28, 2631–2654 (1992).
[Crossref]

Fève, J. P.

B. Boulanger, I. Rousseau, J. P. Fève, M. Maglione, B. Ménaert, and G. Marnier, “Optical Studies of Laser-Induced Gray-Tracking in KTP,” IEEE J. Quantum Electron. 35, 281–286 (1999).
[Crossref]

Freegarde, T.

Fukui, T.

Gavrilovic, P.

Giacobino, E.

Goyal, A. K.

Hall, J. L.

Hänsch, T. W.

T. Freegarde, J. Coutts, J. Walz, D. Leibfried, and T. W. Hänsch, “General analysis of type I second-harmonic generation with elliptical Gaussian beams,” J. Opt. Soc. Am. B 14, 2010–2016 (1997).
[Crossref]

T. W. Hänsch and B. Couillaud, “Laser frequency stabilization by polarization spectroscopy of a reflecting reference cavity,” Opt. Commun. 35, 441–444 (1980).
[Crossref]

Hansson, G.

Holm, J.

Isaenko, L.

Jensen, O. B.

Jundt, D. H.

M.M. Fejer, G. A. Magel, D. H. Jundt, and R. L. Byer,” Quasi-Phase-Matched Second Harmonic Generation: Tuning and Tolerances,” IEEE J. Quantum Electron. 28, 2631–2654 (1992).
[Crossref]

Jungner, P.

Kimble, H. J.

Kleinman, D. A.

G. D. Boyd and D. A. Kleinman, “Parametric Interaction of Focused Gaussian Light Beams,” J. Appl. Phys. 39, 3597–3639 (1968).
[Crossref]

Knauer, A.

A. Knauer, G. Erbert, R. Staske, B. Sumpf, H. Wenzel, and M. Weyers, “High-power 808-nm lasers with a super-large optical cavity,” Semicond. Sci. Technol. 20, 621–624 (2005).
[Crossref]

Kubota, S.

Laurell, F.

Le. Targat, R.

R. Le. Targat, J.-J. Zondy, and P. Lemonde, “75%-Efficiency blue generation from an intracavity PPKTP frequency doubler,” Opt. Commun. 247, 471–481 (2005).
[Crossref]

Leibfried, D.

Lemonde, P.

R. Le. Targat, J.-J. Zondy, and P. Lemonde, “75%-Efficiency blue generation from an intracavity PPKTP frequency doubler,” Opt. Commun. 247, 471–481 (2005).
[Crossref]

Lobanov, S.

Ma, L.-S.

Magel, G. A.

M.M. Fejer, G. A. Magel, D. H. Jundt, and R. L. Byer,” Quasi-Phase-Matched Second Harmonic Generation: Tuning and Tolerances,” IEEE J. Quantum Electron. 28, 2631–2654 (1992).
[Crossref]

Maglione, M.

B. Boulanger, I. Rousseau, J. P. Fève, M. Maglione, B. Ménaert, and G. Marnier, “Optical Studies of Laser-Induced Gray-Tracking in KTP,” IEEE J. Quantum Electron. 35, 281–286 (1999).
[Crossref]

Mao, Y.

Marnier, G.

B. Boulanger, I. Rousseau, J. P. Fève, M. Maglione, B. Ménaert, and G. Marnier, “Optical Studies of Laser-Induced Gray-Tracking in KTP,” IEEE J. Quantum Electron. 35, 281–286 (1999).
[Crossref]

Masuda, H.

Ménaert, B.

B. Boulanger, I. Rousseau, J. P. Fève, M. Maglione, B. Ménaert, and G. Marnier, “Optical Studies of Laser-Induced Gray-Tracking in KTP,” IEEE J. Quantum Electron. 35, 281–286 (1999).
[Crossref]

Pedersen, C.

Petersen, P. M.

Po, H.

Polzik, E. S.

Riis, E.

F. Torabi-Goudarzi and E. Riis, “Efficient cw high-power frequency doubling in periodically poled KTP,” Opt. Commun. 227, 389–403 (2003).
[Crossref]

Risk, W. P.

W. P. Risk et al, Compact Blue-Green lasers (Cambridge Univercity Press, Cambridge, UK, 2003).

Rousseau, I.

B. Boulanger, I. Rousseau, J. P. Fève, M. Maglione, B. Ménaert, and G. Marnier, “Optical Studies of Laser-Induced Gray-Tracking in KTP,” IEEE J. Quantum Electron. 35, 281–286 (1999).
[Crossref]

Scheidt, M.

B. Beier, D. Woll, M. Scheidt, K.-J. Boller, and R. Wallenstein, “Second harmonic generation of the output of an AlGaAs diode oscillator amplifier system in critically phase matched LiB3O5 and β-BaB2O4,” Appl. Phys. Lett. 71, 315–317 (1997).
[Crossref]

Siegman, A. E.

A. E. Siegman, Lasers (University Science, Mill Valley, Calif., 1986).

Singh, S.

Staske, R.

A. Knauer, G. Erbert, R. Staske, B. Sumpf, H. Wenzel, and M. Weyers, “High-power 808-nm lasers with a super-large optical cavity,” Semicond. Sci. Technol. 20, 621–624 (2005).
[Crossref]

Sumpf, B.

A. Knauer, G. Erbert, R. Staske, B. Sumpf, H. Wenzel, and M. Weyers, “High-power 808-nm lasers with a super-large optical cavity,” Semicond. Sci. Technol. 20, 621–624 (2005).
[Crossref]

M. Chi, O. B. Jensen, J. Holm, C. Pedersen, P. E. Andersen, G. Erbert, B. Sumpf, and P. M. Petersen, “Tunable high-power narrow-linewidth semiconductor laser based on an external-cavity tapered amplifier,” Opt. Express 13, 10589–10596 (2005).
[Crossref] [PubMed]

H. Wenzel, B. Sumpf, and G. Erbert, “High-brightness diode lasers,” C. R. Physique 4, 649–661 (2003).
[Crossref]

Torabi-Goudarzi, F.

F. Torabi-Goudarzi and E. Riis, “Efficient cw high-power frequency doubling in periodically poled KTP,” Opt. Commun. 227, 389–403 (2003).
[Crossref]

Vanherzeele, Herman

Villa, F.

Wallenstein, R.

B. Beier, D. Woll, M. Scheidt, K.-J. Boller, and R. Wallenstein, “Second harmonic generation of the output of an AlGaAs diode oscillator amplifier system in critically phase matched LiB3O5 and β-BaB2O4,” Appl. Phys. Lett. 71, 315–317 (1997).
[Crossref]

Walz, J.

Wang, S

Wenzel, H.

A. Knauer, G. Erbert, R. Staske, B. Sumpf, H. Wenzel, and M. Weyers, “High-power 808-nm lasers with a super-large optical cavity,” Semicond. Sci. Technol. 20, 621–624 (2005).
[Crossref]

H. Wenzel, B. Sumpf, and G. Erbert, “High-brightness diode lasers,” C. R. Physique 4, 649–661 (2003).
[Crossref]

Weyers, M.

A. Knauer, G. Erbert, R. Staske, B. Sumpf, H. Wenzel, and M. Weyers, “High-power 808-nm lasers with a super-large optical cavity,” Semicond. Sci. Technol. 20, 621–624 (2005).
[Crossref]

Wiechmann, W.

Woll, D.

B. Beier, D. Woll, M. Scheidt, K.-J. Boller, and R. Wallenstein, “Second harmonic generation of the output of an AlGaAs diode oscillator amplifier system in critically phase matched LiB3O5 and β-BaB2O4,” Appl. Phys. Lett. 71, 315–317 (1997).
[Crossref]

Ye, J.

Yelisseyev, A.

Zondy, J. -J.

Zondy, J.-J.

R. Le. Targat, J.-J. Zondy, and P. Lemonde, “75%-Efficiency blue generation from an intracavity PPKTP frequency doubler,” Opt. Commun. 247, 471–481 (2005).
[Crossref]

Appl. Opt. (1)

Appl. Phys. Lett. (1)

B. Beier, D. Woll, M. Scheidt, K.-J. Boller, and R. Wallenstein, “Second harmonic generation of the output of an AlGaAs diode oscillator amplifier system in critically phase matched LiB3O5 and β-BaB2O4,” Appl. Phys. Lett. 71, 315–317 (1997).
[Crossref]

C. R. Physique (1)

H. Wenzel, B. Sumpf, and G. Erbert, “High-brightness diode lasers,” C. R. Physique 4, 649–661 (2003).
[Crossref]

IEEE J. Quantum Electron. (3)

B. Boulanger, I. Rousseau, J. P. Fève, M. Maglione, B. Ménaert, and G. Marnier, “Optical Studies of Laser-Induced Gray-Tracking in KTP,” IEEE J. Quantum Electron. 35, 281–286 (1999).
[Crossref]

M.M. Fejer, G. A. Magel, D. H. Jundt, and R. L. Byer,” Quasi-Phase-Matched Second Harmonic Generation: Tuning and Tolerances,” IEEE J. Quantum Electron. 28, 2631–2654 (1992).
[Crossref]

A. Ashkin, G. D. Boyd, and J. M. Dziedzic, “Resonant optical second harmonic generation and mixing,” IEEE J. Quantum Electron. 2, 109–124 (1966).
[Crossref]

J. Appl. Phys. (1)

G. D. Boyd and D. A. Kleinman, “Parametric Interaction of Focused Gaussian Light Beams,” J. Appl. Phys. 39, 3597–3639 (1968).
[Crossref]

J. Opt. Soc. Am. B (5)

Opt. Commun. (3)

T. W. Hänsch and B. Couillaud, “Laser frequency stabilization by polarization spectroscopy of a reflecting reference cavity,” Opt. Commun. 35, 441–444 (1980).
[Crossref]

F. Torabi-Goudarzi and E. Riis, “Efficient cw high-power frequency doubling in periodically poled KTP,” Opt. Commun. 227, 389–403 (2003).
[Crossref]

R. Le. Targat, J.-J. Zondy, and P. Lemonde, “75%-Efficiency blue generation from an intracavity PPKTP frequency doubler,” Opt. Commun. 247, 471–481 (2005).
[Crossref]

Opt. Express (1)

Opt. Lett. (3)

Semicond. Sci. Technol. (1)

A. Knauer, G. Erbert, R. Staske, B. Sumpf, H. Wenzel, and M. Weyers, “High-power 808-nm lasers with a super-large optical cavity,” Semicond. Sci. Technol. 20, 621–624 (2005).
[Crossref]

Other (2)

A. E. Siegman, Lasers (University Science, Mill Valley, Calif., 1986).

W. P. Risk et al, Compact Blue-Green lasers (Cambridge Univercity Press, Cambridge, UK, 2003).

Cited By

OSA participates in Crossref's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (4)

Fig. 1.
Fig. 1. Sketch of the experimental setup. The laser source is shown in the top right. HWP, half-wave-plate; Modematching optics, 4 cylindrical lenses (not drawn).
Fig. 2.
Fig. 2. Left: The scanning peaks when the system is operated away from phasematch. The dashed line is the supplied voltage to the piezo. The measurements are done of the leaked pump beam through the piezo mirror. Right: The temperature tuning curve with a fitted sinc2 function. The used pump power is 200 mW. The FWHM value of the fitted sinc2 is 0.44 K.
Fig. 3.
Fig. 3. The second harmonic power measured after the output coupler. The red squares are measured in continuous wave mode; blue triangles are scanning mode results. Solid line is the predicted results based on 4% roundtrip loss, and a single pass conversion efficiency of 1.38%/W.
Fig. 4.
Fig. 4. The conversion efficiency as a function of coupled pump power. Same legend as Fig. 3.

Equations (3)

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

T 1 P in = P c [ 1 ( ( 1 L ) ( 1 T 1 ) ( 1 η P c ) ) 1 2 ] 2 ,
L eff = 1.39 λ π Δ T FWHM [ ( n 2 ω T n ω T ) T = T pm α ( n 2 ω n ω ) ] 1
P 2 ω = 16 π 2 d eff 2 ε 0 c λ ω 3 n ω n 2 ω P ω 2 L h

Metrics