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Applied Optics

Applied Optics

APPLICATIONS-CENTERED RESEARCH IN OPTICS

  • Vol. 38, Iss. 18 — Jun. 20, 1999
  • pp: 3917–3923

Optimal control theory for optical waveguide design: application to Y-branch structures

Dhruv K. Pant, Rob D. Coalson, Marta I. Hernández, and José Campos-Martínez  »View Author Affiliations


Applied Optics, Vol. 38, Issue 18, pp. 3917-3923 (1999)
http://dx.doi.org/10.1364/AO.38.003917


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Abstract

A recently introduced optimal control theory method for optical waveguide design is applied to Y-branch waveguides and Mach–Zehnder modulators. The method simultaneously optimizes many parameters in a chosen design scheme; computational effort scales mildly with the number of parameters considered. Significant improvement in guiding efficiency relative to intuitively reasonable initial parameter choices is obtained in all cases.

© 1999 Optical Society of America

OCIS Codes
(230.1360) Optical devices : Beam splitters
(230.7370) Optical devices : Waveguides
(350.5500) Other areas of optics : Propagation

History
Original Manuscript: December 8, 1998
Revised Manuscript: March 18, 1999
Published: June 20, 1999

Citation
Dhruv K. Pant, Rob D. Coalson, Marta I. Hernández, and José Campos-Martínez, "Optimal control theory for optical waveguide design: application to Y-branch structures," Appl. Opt. 38, 3917-3923 (1999)
http://www.opticsinfobase.org/ao/abstract.cfm?URI=ao-38-18-3917


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References

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  19. Criteria other than output quality can in principle be included in the cost function. Some possibilities were considered in Ref. 5. Here for simplicity we assume that output quality is the only important issue.
  20. Other criteria for optimal guiding are possible, for example, maximization of the integrated beam intensity within the boundaries of the guide at its output. There exists an appropriate projection operator analogous to the one given in Eq. (5) for each optimal guiding criterion.
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  24. The calculation presented in Fig. 8, with five adjustable parameters, required approximately 50 iterations and took approximately 90 min of CPU time on a low-end work station.
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  26. J. S. Cites, P. R. Ashley, “High performance Mach-Zehnder modulators in multiple quantum well GaAs/AlGaAs,” J. Lightwave Technol. 12, 1167–1173 (1994). [CrossRef]

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