OSA's Digital Library

Applied Optics

Applied Optics


  • Vol. 38, Iss. 12 — Apr. 20, 1999
  • pp: 2451–2457

Linear control of the spectral characteristics of wavelength-selective components with a high-index tapered thin-film planar waveguide and a single-mode half-coupler

Alok K. Das and Anwar Hussain  »View Author Affiliations

Applied Optics, Vol. 38, Issue 12, pp. 2451-2457 (1999)

View Full Text Article

Enhanced HTML    Acrobat PDF (204 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



A simple system of linearly tunable fiber–film wavelength-dependent components is demonstrated that includes a linearly tapered high-index thin-film planar waveguide (PWG) evanescently coupled by a single-mode-fiber half-coupler. We present experimental and theoretical results for the linear tuning of spectral responses such as coupled power, resonance position (λ0), and fiber output-light polarization through position shifting of the linearly tapered PWG, in the direction of the propagating light in the fiber, over the half-coupler block. We achieved almost linear control of the spectral response by changing the temperature of mixture-of-oils and overlay-doped poly(methyl methacrylate) PWG’s when the refractive index of the system decreases with temperature. The variation in thickness of the tapered film is along the direction of the interaction length of the system. Linear tapered PWG’s that comprised a mixture of oils, BK7 glass, and overlay-doped PMMA with high refractive indices were fabricated that could operate the device at lower and higher modes. We investigated the dependence of tuning λ0 on the PWG mode. Tuning by shifting of a linear tapered PWG over a fiber half-block is mode dependent, whereas tuning by changing the refractive index of a uniform PWG is mode independent. Wavelength shift Δλ0 is found to decrease with an increase in the resonant PWG mode number m for linearly tapered PWG’s. A fiber-to-asymmetric linear tapered–PWG coupler, which maintains the taper slope to within a specific limit, can function as a linearly tunable polarizer for the light in the fiber.

© 1999 Optical Society of America

OCIS Codes
(060.1810) Fiber optics and optical communications : Buffers, couplers, routers, switches, and multiplexers
(060.2340) Fiber optics and optical communications : Fiber optics components
(120.2440) Instrumentation, measurement, and metrology : Filters
(130.3120) Integrated optics : Integrated optics devices
(230.5440) Optical devices : Polarization-selective devices
(310.6860) Thin films : Thin films, optical properties

Original Manuscript: August 11, 1997
Revised Manuscript: December 4, 1998
Published: April 20, 1999

Alok K. Das and Anwar Hussain, "Linear control of the spectral characteristics of wavelength-selective components with a high-index tapered thin-film planar waveguide and a single-mode half-coupler," Appl. Opt. 38, 2451-2457 (1999)

Sort:  Author  |  Year  |  Journal  |  Reset  


  1. K. McCallion, W. Johnstone, G. Fawcett, “Tunable in-line fiber-optic bandpass filter,” Opt. Lett. 19, 542–544 (1994). [CrossRef] [PubMed]
  2. W. Johnstone, G. Thursby, D. G. Moodie, R. Varshuey, B. Culshaw, “Fiber optic wavelength channel selector with high resolution,” Electron. Lett. 28, 1364–1365 (1992). [CrossRef]
  3. M. Zhang, E. Garmire, “Single-mode fiber–film directional coupler,” J. Lightwave Technol. LT-5, 260–267 (1987). [CrossRef]
  4. A. T. Andreev, K. P. Panajatov, “Wavelength division action of a distributed single-mode fiber-to-symmetrical planar waveguide coupler,” Photon. Technol. Lett. 6, 1238–1240 (1994). [CrossRef]
  5. D. G. Moodie, W. Johnstone, “Wavelength tunability of components based on the evanescent coupling from a side-polished fiber to a high-index-overlay waveguide,” Opt. Lett. 18, 1025–1027 (1993). [CrossRef] [PubMed]
  6. C. A. Millar, M. C. Brierley, S. R. Mallinson, “Exposed-core single-mode fiber channel-dropping filter using a high-index overlay waveguide,” Opt. Lett. 12, 284–286 (1987). [CrossRef] [PubMed]
  7. Y. Cai, T. Mizumoto, Y. Naito, “An effective method for coupling single-mode fiber to thin film waveguide,” J. Lightwave Technol. 9, 577–583 (1991). [CrossRef]
  8. A. T. Andreev, K. P. Panajatov, “Distributed single-mode fiber to single-mode planar waveguide coupler,” J. Lightwave Technol. 11, 1985–1989 (1993). [CrossRef]
  9. D. Marcuse, “Investigation of coupling between a fiber and an infinite slab,” J. Lightwave Technol. 7, 122–130 (1989). [CrossRef]
  10. A. N. Miliou, R. Srivastava, R. V. Ramaswamy, “A 1.3 µm directional coupler polarization splitter by ion exchange,” J. Lightwave Technol. 11, 220–225 (1993). [CrossRef]
  11. K. Morishita, K. Aso, “Fiber loop polarizers using a fused taper coupler,” J. Lightwave Technol. 12, 634–637 (1994). [CrossRef]
  12. A. M. Scheggi, M. Brenci, G. Conforti, R. Falciai, “Optical-fibre thermometer for medical use,” Proc. Inst. Electr. Eng. Part H 131, 270–272 (1984).
  13. K. P. Panajotov, “Polarisation properties of a fiber-to-asymmetric planar waveguide coupler,” J. Lightwave Technol. 12, 983–988 (1994). [CrossRef]
  14. A. K. Das, A. Hussain, “Single-mode fiber–linearly tapered planar waveguide tunable coupler,” Appl. Opt. 36, 6822–6827 (1997). [CrossRef]
  15. D. Marcuse, Light Transmission Optics, 2nd ed. (Von Nostrand Reinhold, New York, 1982).
  16. C. Liao, G. I. Stegeman, C. T. Seaton, R. L. Shoemaker, J. D. Valera, “Nonlinear distributed waveguide couplers,” J. Opt. Soc. Am. A 12, 590–594 (1985). [CrossRef]
  17. M. J. F. Digonnet, H. J. Shaw, “Analysis of a tunable single mode optical fiber coupler,” IEEE J. Quantum Electron. QE-18, 746–754 (1982). [CrossRef]
  18. H. Nishihara, M. Haruna, T. Sahara, Optical Integrated Circuits (McGraw-Hill, New York, 1989).
  19. L. A. Hornak, Polymers for Lightwave and Integrated Optics (Marcel Dekker, New York, 1992).
  20. A. K. Das, A. K. Ganguly, “Efficient method of coupling from a single-mode fiber to a thin film waveguide,” Opt. Lett. 19, 2110–2112 (1994). [CrossRef] [PubMed]
  21. R. S. Mozhrefzadeh, M. D. Radcliffe, T. C. Lee, S. K. Mohapatra, “Temperature dependence of index of refraction of polymer waveguides,” J. Lightwave Technol. 10, 420–425 (1992). [CrossRef]

Cited By

Alert me when this paper is cited

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.


Fig. 1 Fig. 2 Fig. 3
Fig. 4 Fig. 5

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited