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Optics Express

Optics Express

  • Editor: Andrew M. Weiner
  • Vol. 21, Iss. 12 — Jun. 17, 2013
  • pp: 14223–14243

Transformation inverse design

David Liu, Lucas H. Gabrielli, Michal Lipson, and Steven G. Johnson  »View Author Affiliations

Optics Express, Vol. 21, Issue 12, pp. 14223-14243 (2013)

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We present a new technique for the design of transformation-optics devices based on large-scale optimization to achieve the optimal effective isotropic dielectric materials within prescribed index bounds, which is computationally cheap because transformation optics circumvents the need to solve Maxwell’s equations at each step. We apply this technique to the design of multimode waveguide bends (realized experimentally in a previous paper) and mode squeezers, in which all modes are transported equally without scattering. In addition to the optimization, a key point is the identification of the correct boundary conditions to ensure reflectionless coupling to untransformed regions while allowing maximum flexibility in the optimization. Many previous authors in transformation optics used a certain kind of quasiconformal map which overconstrained the problem by requiring that the entire boundary shape be specified a priori while at the same time underconstraining the problem by employing “slipping” boundary conditions that permit unwanted interface reflections.

© 2013 OSA

OCIS Codes
(000.3860) General : Mathematical methods in physics
(120.4570) Instrumentation, measurement, and metrology : Optical design of instruments
(130.2790) Integrated optics : Guided waves
(160.3918) Materials : Metamaterials

ToC Category:
Physical Optics

Original Manuscript: April 8, 2013
Revised Manuscript: May 25, 2013
Manuscript Accepted: May 28, 2013
Published: June 7, 2013

David Liu, Lucas H. Gabrielli, Michal Lipson, and Steven G. Johnson, "Transformation inverse design," Opt. Express 21, 14223-14243 (2013)

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