Abstract

In this paper, we propose and demonstrate the use of multilayered (laminated) waveguides for increasing the available gain spectrum of sol–gel amplifiers. Experimental investigations of the effects of phosphorus codoping on the amplifier spectral characteristics and fluorescence decay are also presented. We demonstrate that the shape of the erbium emission cross section, for aluminophosphosilicate amplifiers, has a minor dependence on the amount of phosphorus doping and that spectral benefits are only achieved for aluminosilicate amplifiers, albeit with low levels of erbium inversion. Laminated amplifiers, consisting of alternating layers of two compositions, are shown to display novel spectral characteristics that cannot be obtained by the use of single composition cores. Internal gain, which is demonstrated for this device, also suggests that erbium inversion can be maintained at relatively high levels. Experimental results are supported by numerical analysis, and a 20-nm bandwidth increase is observed for laminated amplifiers, with gain levels up to 1.4 dB/cm indicated, when processing conditions are optimized.

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  1. D. Barbier, P. Bruno, C. Cassagnettes, M. Trouillon, R. L. Hyde, A. Kevorkian, J. M. P. Deleveauxl, "Net gain of 27 dB with 8.6-cm-long Er/Yb doped glass planar amplifier," OFC Tech. Dig. (1998) pp. 45-48.
  2. P. Camy, J. E. Román, F. W. Willems, M. Hempstead, J. S. Wilkinson, J. C. van der Plaats, A. M. J. Koonen, A. Béguin, C. Prel, C. Lerminiaux, "Ion-exchanged planar lossless splitter at 1.5 μm," Electron. Lett. 32, 321-323 (1996).
  3. J. Hübner, S. Guldberg-Kjaer, M. Dyngaard, Y. Shen, C. L. Thomsen, S. Balslev, C. Jensen, D. Zauner, T. Feuchter, "Planar Er and Yb doped amplifiers and lasers," Appl. Phys. B, Photophys. Laser Chem. 73, 435-438 (2001).
  4. F. D. Patel, S. DiCarolis, P. Lum, S. Venkatesh, J. N. Miller, "A compact high performance optical waveguide amplifier," IEEE Photon. Technol. Lett. 16, 2607-2609 (2004).
  5. Y. C. Yan, A. J. Faber, H. de Waal, P. G. Kik, A. Polman, "Erbium-doped phosphate glass waveguide on silicon with 4.1 dB/cm gain at 1.535 μm," Appl. Phys. Lett. 71, 2922-2924 (1997).
  6. E. Desurvire, Erbium Doped Fiber Amplifiers: Principles and Applications (Wiley-Interscience, 1994).
  7. H. Ono, M. Yamada, Y. Ohishi, "Gain-flattened Er-doped fiber amplifier for WDM signal in the 1.57–1.6 μm wavelength region," IEEE Photon. Technol. Lett. 9, 596-598 (1997).
  8. M. Yamada, "Gain-flattened tellurite-based EDFA with flat amplification bandwidth of 76 nm," IEEE Photon. Technol. Lett. 10, 1244-1246 (1998).
  9. Y. Ohishi, "Gain characteristics of tellurite-based erbium doped fiber amplifiers for 1.5 μm broadband amplification," Opt. Lett. 23, 274-276 (1998).
  10. S. K. Liaw, "Dynamic power-equalised EDFA module based on strain tuneable Bragg gratings," IEEE Photon. Technol. Lett. 11, 797-799 (1999).
  11. L. R. Chen, "Transmission edge filters for power equalisation of EDFA's," IEEE Photon. Technol. Lett. 12, 822-824 (2000).
  12. W. J. Miniscalco, "Erbium-doped glasses for fiber amplifiers at 1500 nm," J. Lightw. Technol. 9, 234-250 (1991).
  13. K. Arai, H. Namikawa, K. Kumata, T. Honda, "Aluminium or phosphorus co-doping effects on the fluorescence and structural properties of neodymium-doped silica glass," J. Appl. Phys. 59, 3430-3436 (1986).
  14. K. Hattori, T. Kitakawa, M. Oguma, H. Okazaki, Y. Ohmori, "Optical amplification in Er+3 doped P2O 5-SiO2 planar waveguides," J. Appl. Phys. 80, 5301-5308 (1996).
  15. W. Huang, R. R. A. Syms, E. M. Yeatman, M. M. Ahmad, T. V. Clap, S. M. Ojha, "Fiber–device–fiber gain from a sol–gel erbium-doped waveguide amplifier ," IEEE Photon. Technol. Lett. 14, 959-961 (2002).
  16. E. M. Yeatman, M. M. Ahmad, O. McCarthy, A. Vannucci, P. Gastaldo, D. Barbier, D. Mongardien, C. Moronvalle, "Optical gain in Er-doped SiO2 - TiO2 waveguides fabricated by the sol–gel technique," Opt. Commun. 164, 19-25 (1999).
  17. W. Huang, R. R. A. Syms, "Sol–gel silica on silicon buried channel EDWA's," J. Lightw. Technol. 21, 1339-1349 (2003).
  18. K. Solehmainen, M. Kapulainen, P. Heimala, K. Polamo, "Erbium doped waveguides fabricated with atomic layer deposition method," IEEE Photon. Technol. Lett. 16, 194-196 (2004).
  19. A. Laliotis, E. M. Yeatman, M. M. Ahmad, W. Huang, "Molecular homogeneity in erbium-doped sol–gel waveguide amplifiers," IEEE J. Quantum Electron. 40, 805-814 (2004).
  20. M. W. Sckerl, S. Guldberg-Kjaer, M. Rysholt Poulsen, P. Shi, J. Chevallier, "Precipitate coarsening and self organization in erbium-doped silica," Phys. Rev. B, Condens. Matter 59, 13 494-13 497 (1999).
  21. R. R. A. Syms, A. S. Holmes, W. Huang, V. M. Schneider, M. Green, "Development of the SC-RTA process for fabrication of sol–gel based silica-on-silicon integrated optic components," J. Sol-Gel Sci. Technol. 13, 509-516 (1998).
  22. R. R. Thomson, H. T. Bookey, H. Ur-Rehman, S. Liu, N. Suyal, A. K. Kar, "Optically active erbium-doped waveguides fabricated using a single sol–gel deposition technique," J. Lightw. Technol. 23, 4249-4256 (2005).
  23. E. M. Yeatman, M. M. Ahmad, O. McCarthy, "Sol–gel fabrication of rare-earth photonic components," J. Sol-Gel Sci. Technol. 19, 231-236 (2000).
  24. R. R. A. Syms, W. Huang, V. M. Schneider, "Optimisation of borophosphosilicate glass compositions for silica-on-silicon integrated optical circuits fabricated by the sol–gel process," Electron. Lett. 32, 1233-1234 (1996).
  25. M. Born, E. Wolf, Principles of Optics (Cambridge Univ. Press, 1997).
  26. M. A. Fardad, E. M. Yeatman, E. J. C. Dawnay, M. Green, F. Horowitz, "Effects of H2O on structure of acid catalysed SIO2 sol–gel films," J. Non-Cryst. Solids 183, 260-267 (1995).
  27. A. Laliotis, E. M. Yeatman, "Consolidation and homogeneity of erbium doped waveguide amplifiers," Conf. Lasers and Electro-Optics/Int. Council Quantum Electronics PhAST San FranciscoCA (2004) Paper CTuS2.
  28. J. Laegsgaard, "Dissolution of rare-earth clusters in SIO2 by Al codoping: A microscopic model," Phys. Rev. B, Condens. Matter 65, 174114-1-174114-10 (2002).
  29. J. Philipsen, P. Gastaldo, C. Cassagnettes, D. Barbier, A. Kevorkian, A. Yeniay, "Self-referenced Q-switched pump-probe transmission experiment for the determination of the degree of clustering in Er-doped planar waveguides," Proc. Opt. Amplifiers and Their Appl., OSA Trends Opt. Photon. (1999) pp. 80-83.
  30. G. Nykolak, P. C. Becker, J. Shmulovitch, Y. H. Wong, D. J. DiGiovanni, A. J. Bruce, "Concentration dependant 4I13/2 lifetimes in Er-doped fibers and Er-doped planar waveguides," IEEE Photon. Technol. Lett. 5, 1014-1016 (1993).
  31. W. Huang, R. R. A. Syms, "Analysis of folded erbium-doped planar waveguide amplifiers by the method of lines," J. Lightw. Technol. 17, 2658-2664 (1999).
  32. A. Laliotis, E. M. Yeatman, S. J. Al-Bader, "Modelling signal and ASE evolution in erbium doped amplifiers by the method of lines ," J. Lightw. Technol. 24, 1589-1600 (2006).
  33. F. Di Pasquale, C. W. Pitt, "Improved gain performance characteristics in high concentration Er/Yb codoped glass waveguide amplifiers," IEEE J. Quantum Electron. 30, 2127-2131 (1994).
  34. F. Di Pasquale, M. Federighi, "Modelling of uniform and pair induced upconversion mechanisms in high concentration erbium doped silica waveguides," J. Lightw. Technol. 13, 1858-1864 (1995).
  35. O. Lumholt, T. Rasmussen, A. Bjarklev, "Modelling of extremely high concentration erbium-doped silica waveguides," Electron. Lett. 29, 495-496 (1993).
  36. C. Strohhofer, A. Polman, "Relationship between concentration in Er3+ - Yb3+ doped waveguide amplifiers," J. Appl. Phys. 90, 4314-4320 (2001).

2006

A. Laliotis, E. M. Yeatman, S. J. Al-Bader, "Modelling signal and ASE evolution in erbium doped amplifiers by the method of lines ," J. Lightw. Technol. 24, 1589-1600 (2006).

2005

R. R. Thomson, H. T. Bookey, H. Ur-Rehman, S. Liu, N. Suyal, A. K. Kar, "Optically active erbium-doped waveguides fabricated using a single sol–gel deposition technique," J. Lightw. Technol. 23, 4249-4256 (2005).

2004

K. Solehmainen, M. Kapulainen, P. Heimala, K. Polamo, "Erbium doped waveguides fabricated with atomic layer deposition method," IEEE Photon. Technol. Lett. 16, 194-196 (2004).

A. Laliotis, E. M. Yeatman, M. M. Ahmad, W. Huang, "Molecular homogeneity in erbium-doped sol–gel waveguide amplifiers," IEEE J. Quantum Electron. 40, 805-814 (2004).

F. D. Patel, S. DiCarolis, P. Lum, S. Venkatesh, J. N. Miller, "A compact high performance optical waveguide amplifier," IEEE Photon. Technol. Lett. 16, 2607-2609 (2004).

2003

W. Huang, R. R. A. Syms, "Sol–gel silica on silicon buried channel EDWA's," J. Lightw. Technol. 21, 1339-1349 (2003).

2002

W. Huang, R. R. A. Syms, E. M. Yeatman, M. M. Ahmad, T. V. Clap, S. M. Ojha, "Fiber–device–fiber gain from a sol–gel erbium-doped waveguide amplifier ," IEEE Photon. Technol. Lett. 14, 959-961 (2002).

J. Laegsgaard, "Dissolution of rare-earth clusters in SIO2 by Al codoping: A microscopic model," Phys. Rev. B, Condens. Matter 65, 174114-1-174114-10 (2002).

2001

C. Strohhofer, A. Polman, "Relationship between concentration in Er3+ - Yb3+ doped waveguide amplifiers," J. Appl. Phys. 90, 4314-4320 (2001).

J. Hübner, S. Guldberg-Kjaer, M. Dyngaard, Y. Shen, C. L. Thomsen, S. Balslev, C. Jensen, D. Zauner, T. Feuchter, "Planar Er and Yb doped amplifiers and lasers," Appl. Phys. B, Photophys. Laser Chem. 73, 435-438 (2001).

2000

E. M. Yeatman, M. M. Ahmad, O. McCarthy, "Sol–gel fabrication of rare-earth photonic components," J. Sol-Gel Sci. Technol. 19, 231-236 (2000).

L. R. Chen, "Transmission edge filters for power equalisation of EDFA's," IEEE Photon. Technol. Lett. 12, 822-824 (2000).

1999

S. K. Liaw, "Dynamic power-equalised EDFA module based on strain tuneable Bragg gratings," IEEE Photon. Technol. Lett. 11, 797-799 (1999).

M. W. Sckerl, S. Guldberg-Kjaer, M. Rysholt Poulsen, P. Shi, J. Chevallier, "Precipitate coarsening and self organization in erbium-doped silica," Phys. Rev. B, Condens. Matter 59, 13 494-13 497 (1999).

E. M. Yeatman, M. M. Ahmad, O. McCarthy, A. Vannucci, P. Gastaldo, D. Barbier, D. Mongardien, C. Moronvalle, "Optical gain in Er-doped SiO2 - TiO2 waveguides fabricated by the sol–gel technique," Opt. Commun. 164, 19-25 (1999).

W. Huang, R. R. A. Syms, "Analysis of folded erbium-doped planar waveguide amplifiers by the method of lines," J. Lightw. Technol. 17, 2658-2664 (1999).

1998

M. Yamada, "Gain-flattened tellurite-based EDFA with flat amplification bandwidth of 76 nm," IEEE Photon. Technol. Lett. 10, 1244-1246 (1998).

Y. Ohishi, "Gain characteristics of tellurite-based erbium doped fiber amplifiers for 1.5 μm broadband amplification," Opt. Lett. 23, 274-276 (1998).

R. R. A. Syms, A. S. Holmes, W. Huang, V. M. Schneider, M. Green, "Development of the SC-RTA process for fabrication of sol–gel based silica-on-silicon integrated optic components," J. Sol-Gel Sci. Technol. 13, 509-516 (1998).

1997

Y. C. Yan, A. J. Faber, H. de Waal, P. G. Kik, A. Polman, "Erbium-doped phosphate glass waveguide on silicon with 4.1 dB/cm gain at 1.535 μm," Appl. Phys. Lett. 71, 2922-2924 (1997).

H. Ono, M. Yamada, Y. Ohishi, "Gain-flattened Er-doped fiber amplifier for WDM signal in the 1.57–1.6 μm wavelength region," IEEE Photon. Technol. Lett. 9, 596-598 (1997).

1996

P. Camy, J. E. Román, F. W. Willems, M. Hempstead, J. S. Wilkinson, J. C. van der Plaats, A. M. J. Koonen, A. Béguin, C. Prel, C. Lerminiaux, "Ion-exchanged planar lossless splitter at 1.5 μm," Electron. Lett. 32, 321-323 (1996).

K. Hattori, T. Kitakawa, M. Oguma, H. Okazaki, Y. Ohmori, "Optical amplification in Er+3 doped P2O 5-SiO2 planar waveguides," J. Appl. Phys. 80, 5301-5308 (1996).

R. R. A. Syms, W. Huang, V. M. Schneider, "Optimisation of borophosphosilicate glass compositions for silica-on-silicon integrated optical circuits fabricated by the sol–gel process," Electron. Lett. 32, 1233-1234 (1996).

1995

M. A. Fardad, E. M. Yeatman, E. J. C. Dawnay, M. Green, F. Horowitz, "Effects of H2O on structure of acid catalysed SIO2 sol–gel films," J. Non-Cryst. Solids 183, 260-267 (1995).

F. Di Pasquale, M. Federighi, "Modelling of uniform and pair induced upconversion mechanisms in high concentration erbium doped silica waveguides," J. Lightw. Technol. 13, 1858-1864 (1995).

1994

F. Di Pasquale, C. W. Pitt, "Improved gain performance characteristics in high concentration Er/Yb codoped glass waveguide amplifiers," IEEE J. Quantum Electron. 30, 2127-2131 (1994).

1993

O. Lumholt, T. Rasmussen, A. Bjarklev, "Modelling of extremely high concentration erbium-doped silica waveguides," Electron. Lett. 29, 495-496 (1993).

G. Nykolak, P. C. Becker, J. Shmulovitch, Y. H. Wong, D. J. DiGiovanni, A. J. Bruce, "Concentration dependant 4I13/2 lifetimes in Er-doped fibers and Er-doped planar waveguides," IEEE Photon. Technol. Lett. 5, 1014-1016 (1993).

1991

W. J. Miniscalco, "Erbium-doped glasses for fiber amplifiers at 1500 nm," J. Lightw. Technol. 9, 234-250 (1991).

1986

K. Arai, H. Namikawa, K. Kumata, T. Honda, "Aluminium or phosphorus co-doping effects on the fluorescence and structural properties of neodymium-doped silica glass," J. Appl. Phys. 59, 3430-3436 (1986).

Appl. Phys. B, Photophys. Laser Chem.

J. Hübner, S. Guldberg-Kjaer, M. Dyngaard, Y. Shen, C. L. Thomsen, S. Balslev, C. Jensen, D. Zauner, T. Feuchter, "Planar Er and Yb doped amplifiers and lasers," Appl. Phys. B, Photophys. Laser Chem. 73, 435-438 (2001).

Appl. Phys. Lett.

Y. C. Yan, A. J. Faber, H. de Waal, P. G. Kik, A. Polman, "Erbium-doped phosphate glass waveguide on silicon with 4.1 dB/cm gain at 1.535 μm," Appl. Phys. Lett. 71, 2922-2924 (1997).

Electron. Lett.

P. Camy, J. E. Román, F. W. Willems, M. Hempstead, J. S. Wilkinson, J. C. van der Plaats, A. M. J. Koonen, A. Béguin, C. Prel, C. Lerminiaux, "Ion-exchanged planar lossless splitter at 1.5 μm," Electron. Lett. 32, 321-323 (1996).

O. Lumholt, T. Rasmussen, A. Bjarklev, "Modelling of extremely high concentration erbium-doped silica waveguides," Electron. Lett. 29, 495-496 (1993).

R. R. A. Syms, W. Huang, V. M. Schneider, "Optimisation of borophosphosilicate glass compositions for silica-on-silicon integrated optical circuits fabricated by the sol–gel process," Electron. Lett. 32, 1233-1234 (1996).

IEEE J. Quantum Electron.

A. Laliotis, E. M. Yeatman, M. M. Ahmad, W. Huang, "Molecular homogeneity in erbium-doped sol–gel waveguide amplifiers," IEEE J. Quantum Electron. 40, 805-814 (2004).

F. Di Pasquale, C. W. Pitt, "Improved gain performance characteristics in high concentration Er/Yb codoped glass waveguide amplifiers," IEEE J. Quantum Electron. 30, 2127-2131 (1994).

IEEE Photon. Technol. Lett.

G. Nykolak, P. C. Becker, J. Shmulovitch, Y. H. Wong, D. J. DiGiovanni, A. J. Bruce, "Concentration dependant 4I13/2 lifetimes in Er-doped fibers and Er-doped planar waveguides," IEEE Photon. Technol. Lett. 5, 1014-1016 (1993).

F. D. Patel, S. DiCarolis, P. Lum, S. Venkatesh, J. N. Miller, "A compact high performance optical waveguide amplifier," IEEE Photon. Technol. Lett. 16, 2607-2609 (2004).

H. Ono, M. Yamada, Y. Ohishi, "Gain-flattened Er-doped fiber amplifier for WDM signal in the 1.57–1.6 μm wavelength region," IEEE Photon. Technol. Lett. 9, 596-598 (1997).

M. Yamada, "Gain-flattened tellurite-based EDFA with flat amplification bandwidth of 76 nm," IEEE Photon. Technol. Lett. 10, 1244-1246 (1998).

S. K. Liaw, "Dynamic power-equalised EDFA module based on strain tuneable Bragg gratings," IEEE Photon. Technol. Lett. 11, 797-799 (1999).

L. R. Chen, "Transmission edge filters for power equalisation of EDFA's," IEEE Photon. Technol. Lett. 12, 822-824 (2000).

W. Huang, R. R. A. Syms, E. M. Yeatman, M. M. Ahmad, T. V. Clap, S. M. Ojha, "Fiber–device–fiber gain from a sol–gel erbium-doped waveguide amplifier ," IEEE Photon. Technol. Lett. 14, 959-961 (2002).

K. Solehmainen, M. Kapulainen, P. Heimala, K. Polamo, "Erbium doped waveguides fabricated with atomic layer deposition method," IEEE Photon. Technol. Lett. 16, 194-196 (2004).

J. Appl. Phys.

K. Arai, H. Namikawa, K. Kumata, T. Honda, "Aluminium or phosphorus co-doping effects on the fluorescence and structural properties of neodymium-doped silica glass," J. Appl. Phys. 59, 3430-3436 (1986).

K. Hattori, T. Kitakawa, M. Oguma, H. Okazaki, Y. Ohmori, "Optical amplification in Er+3 doped P2O 5-SiO2 planar waveguides," J. Appl. Phys. 80, 5301-5308 (1996).

C. Strohhofer, A. Polman, "Relationship between concentration in Er3+ - Yb3+ doped waveguide amplifiers," J. Appl. Phys. 90, 4314-4320 (2001).

J. Lightw. Technol.

F. Di Pasquale, M. Federighi, "Modelling of uniform and pair induced upconversion mechanisms in high concentration erbium doped silica waveguides," J. Lightw. Technol. 13, 1858-1864 (1995).

W. Huang, R. R. A. Syms, "Analysis of folded erbium-doped planar waveguide amplifiers by the method of lines," J. Lightw. Technol. 17, 2658-2664 (1999).

A. Laliotis, E. M. Yeatman, S. J. Al-Bader, "Modelling signal and ASE evolution in erbium doped amplifiers by the method of lines ," J. Lightw. Technol. 24, 1589-1600 (2006).

W. J. Miniscalco, "Erbium-doped glasses for fiber amplifiers at 1500 nm," J. Lightw. Technol. 9, 234-250 (1991).

W. Huang, R. R. A. Syms, "Sol–gel silica on silicon buried channel EDWA's," J. Lightw. Technol. 21, 1339-1349 (2003).

R. R. Thomson, H. T. Bookey, H. Ur-Rehman, S. Liu, N. Suyal, A. K. Kar, "Optically active erbium-doped waveguides fabricated using a single sol–gel deposition technique," J. Lightw. Technol. 23, 4249-4256 (2005).

J. Non-Cryst. Solids

M. A. Fardad, E. M. Yeatman, E. J. C. Dawnay, M. Green, F. Horowitz, "Effects of H2O on structure of acid catalysed SIO2 sol–gel films," J. Non-Cryst. Solids 183, 260-267 (1995).

J. Sol-Gel Sci. Technol.

E. M. Yeatman, M. M. Ahmad, O. McCarthy, "Sol–gel fabrication of rare-earth photonic components," J. Sol-Gel Sci. Technol. 19, 231-236 (2000).

R. R. A. Syms, A. S. Holmes, W. Huang, V. M. Schneider, M. Green, "Development of the SC-RTA process for fabrication of sol–gel based silica-on-silicon integrated optic components," J. Sol-Gel Sci. Technol. 13, 509-516 (1998).

Opt. Commun.

E. M. Yeatman, M. M. Ahmad, O. McCarthy, A. Vannucci, P. Gastaldo, D. Barbier, D. Mongardien, C. Moronvalle, "Optical gain in Er-doped SiO2 - TiO2 waveguides fabricated by the sol–gel technique," Opt. Commun. 164, 19-25 (1999).

Opt. Lett.

Phys. Rev. B, Condens. Matter

J. Laegsgaard, "Dissolution of rare-earth clusters in SIO2 by Al codoping: A microscopic model," Phys. Rev. B, Condens. Matter 65, 174114-1-174114-10 (2002).

M. W. Sckerl, S. Guldberg-Kjaer, M. Rysholt Poulsen, P. Shi, J. Chevallier, "Precipitate coarsening and self organization in erbium-doped silica," Phys. Rev. B, Condens. Matter 59, 13 494-13 497 (1999).

Other

A. Laliotis, E. M. Yeatman, "Consolidation and homogeneity of erbium doped waveguide amplifiers," Conf. Lasers and Electro-Optics/Int. Council Quantum Electronics PhAST San FranciscoCA (2004) Paper CTuS2.

M. Born, E. Wolf, Principles of Optics (Cambridge Univ. Press, 1997).

J. Philipsen, P. Gastaldo, C. Cassagnettes, D. Barbier, A. Kevorkian, A. Yeniay, "Self-referenced Q-switched pump-probe transmission experiment for the determination of the degree of clustering in Er-doped planar waveguides," Proc. Opt. Amplifiers and Their Appl., OSA Trends Opt. Photon. (1999) pp. 80-83.

D. Barbier, P. Bruno, C. Cassagnettes, M. Trouillon, R. L. Hyde, A. Kevorkian, J. M. P. Deleveauxl, "Net gain of 27 dB with 8.6-cm-long Er/Yb doped glass planar amplifier," OFC Tech. Dig. (1998) pp. 45-48.

E. Desurvire, Erbium Doped Fiber Amplifiers: Principles and Applications (Wiley-Interscience, 1994).

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