OSA's Digital Library

Journal of Lightwave Technology

Journal of Lightwave Technology


  • Vol. 25, Iss. 6 — Jun. 1, 2007
  • pp: 1588–1593

Soft-Proton-Exchange Tapers for Low Insertion-Loss LiNbO3 Devices

Davide Castaldini, Paolo Bassi, Sorin Tascu, Pierre Aschieri, Marc P. De Micheli, and Pascal Baldi

Journal of Lightwave Technology, Vol. 25, Issue 6, pp. 1588-1593 (2007)

View Full Text Article

Acrobat PDF (220 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools

  • Export Citation/Save Click for help


We present the results of an experimental study of waveguide tapers realized in LiNbO3 using the soft-proton-exchange process and the waveguide segmentation technique. Measurements show that they can be favorably introduced between the nonlinear or electrooptic part of the components, which require strong mode confinement to increase efficiency, and the coupling section with a standard optical fiber, which requires low mode confinement in order to have low coupling losses. These tapers allow almost lossless mode-shape transformation. Preliminary results show that they allow reducing the coupling losses by up to 0.7 dB, thus proving the practical interest of the approach.

© 2007 IEEE

Davide Castaldini, Paolo Bassi, Sorin Tascu, Pierre Aschieri, Marc P. De Micheli, and Pascal Baldi, "Soft-Proton-Exchange Tapers for Low Insertion-Loss LiNbO3 Devices," J. Lightwave Technol. 25, 1588-1593 (2007)

Sort:  Year  |  Journal  |  Reset


  1. R. C. Alferness, V. R. Ramaswamy, M. D. Divino, L. L. Buhl, "Efficient single-mode fiber to titanium diffused lithium niobate waveguide coupling for λ = 1.32 μm," IEEE J. Quantum Electron. QE-18, 1807-1813 (1982).
  2. P. G. Suchoski, R. V. Ramaswamy, "Constant-width variable-index transition for efficient Ti:LiNbO3 waveguide-fiber coupling," J. Lightw. Technol. LT-5, 1246-1251 (1987).
  3. K. Kasaya, O. Mitomi, M. Naganuma, Y. Kondo, Y. Noguchi, "A simple laterally tapered waveguide for low-loss coupling to single-mode fibers," IEEE Photon. Technol. Lett. 5, 345-347 (1993).
  4. B. Luyssaert, P. Vandersteegen, R. Baets, "Efficient nonadiabatic planar waveguide tapers," J. Lightw. Technol. 23, 2462-2468 (2005).
  5. F. Van Laere, D. Taillaert, D. Van Thourhout, R. Baets, "Compact and highly efficient grating couplers between optical fiber and nanophotonic waveguides in bonded InP-membranes," 32nd Eur. Conf. Optical Commun. (ECOC) CannesFrance (2006) Paper Tu1.4.5.
  6. M. H. Chou, M. A. Arbore, M. M. Fejer, "Adiabatically tapered periodic segmentation of channel waveguides for mode-size transformation and fundamental mode excitation," Opt. Lett. 21, 794-796 (1996).
  7. F. Dorgeuille, B. Mersali, S. Francois, G. Herve-Gruyer, M. Filoche, "Spot size transformer with a periodically segmented waveguide based on InP," Opt. Lett. 20, 581-583 (1995).
  8. M. M. Spuhler, B. J. Offrein, G. Bona, R. Germann, I. Massarek, D. Ern, "A very short planar silica spot-size converter using a nonperiodic segmented waveguide ," J. Lightw. Technol. 16, 1680-1685 (1998).
  9. Z. Weissman, A. Hardy, "2-D Mode tapering via tapered channel waveguide segmentation," Electron. Lett. 28, 1514-1516 (1992).
  10. Z. Weissman, I. Hendel, "Analysis of periodically segmented waveguide mode expanders," J. Lightw. Technol. 13, 2053-2058 (1995).
  11. M. Yanagisawa, Y. Yamada, M. Kobayashi, "Low-loss and large tolerance fiber coupling of high-Δ silica waveguides by local mode-field conversion," IEEE Photon. Technol. Lett. 5, 433-435 (1993).
  12. O. Alibart, S. Tanzilli, D. B. Ostrowsky, P. Baldi, "Guided wave technology for telecom wavelength heralded single photon source," Opt. Lett. 30, 1539-1541 (2005).
  13. J. R. Carruthers, I. P. Kaminow, L. W. Stulz, "Diffusion kinetics and optical waveguiding properties of outdiffused layers in lithium niobate and lithium tantalite," Appl. Opt. 13, 2333-2342 (1974).
  14. G. J. Griffiths, R. J. Esdaile, "Analysis of titanium diffused planar optical waveguides in lithium niobate," IEEE J. Quantum Electron. QE-20, 149-159 (1984).
  15. M. L. Shah, "Optical waveguides in LiNbO3 by ion exchange technique," Appl. Phys. Lett. 26, 652-653 (1975).
  16. J. L. Jackel, C. E. Rice, J. J. Veselka, "Proton exchange for high-index waveguides in LiNbO3," Appl. Phys. Lett. 41, 607-608 (1982).
  17. M. L. Bortz, M. M. Fejer, "Annealed proton-exchanged LiNbO3 waveguides ," Opt. Lett. 16, 1844-1846 (1991).
  18. L. Chanvillard, P. Aschieri, P. Baldi, D. B. Ostrowsky, M. De Micheli, L. Huang, D. J. Bamford, "Soft proton exchange on PPLN: A simple waveguide fabrication process for highly efficient non-linear interactions," Appl. Phys. Lett. 76, 1089-1091 (2000).
  19. Y. N. Korkishko, V. A. Fedorov, "Structural phase diagram of HxLi1-xNbO3 waveguides: The correlation between optical and structural properties," IEEE J. Sel. Topics Quantum Electron. 2, 187-196 (1996).
  20. C. Canali, A. Carnera, G. della Mea, P. Mazzoldi, S. M. Al Shukri, A. C. G. Nutt, R. M. De La Rue, "Structural characterization of proton exchanged LiNbO3 optical waveguides," J. Appl. Phys. 59, 2643-2649 (1986).
  21. Y. N. Korkishko, V. A. Fedorov, E. A. Baranov, M. V. Proyaeva, T. V. Morozova, F. Caccavale, F. Segato, C. Sada, S. M. Kostritskii, "Characterization of alpha-phase soft proton-exchanged LiNbO3 optical waveguides," J. Opt. Soc. Amer. A, Opt. Image Sci. 18, 1186-1191 (2001).
  22. Z. Weissman, A. Hardy, "Modes of periodically segmented waveguides," J. Lightw. Technol. 11, 1831-1838 (1993).
  23. D. Ortega, J. M. Aldariz, J. M. Arnold, J. S. Aitchison, "Analysis of ‘Quasi-Modes’ in periodic segmented waveguides," J. Lightw. Technol. 17, 369-375 (1999).
  24. P. Aschieri, V. Rastogi, L. Chanvillard, P. Baldi, M. De Micheli, D. B. Ostrowsky, G. Bellanca, P. Bassi, K. Thyagarajan, M. R. Shenoy, "Experimental observation of longitudinal modulation of mode fields in periodically segmented waveguides," Appl. Opt. 38, 5734-5737 (1999).
  25. R. Regener, W. Sohler, "Loss in low-finesse Ti:LiNbO3 optical waveguide resonators," Appl. Phys. B, Photophys. Laser Chem. 36, 143-147 (1985).
  26. D. Hannappe, J. Desbois, "Original method for measurement of optical mode fields," Appl. Opt. 35, 659-662 (1996).
  27. F. Fogli, G. Bellanca, P. Bassi, I. Madden, W. Johnstone, "Highly efficient full vectorial 3D BPM modeling of polished fiber couplers," J. Lightw. Technol. 17, 136-143 (1999).

Cited By

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited