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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 19, Iss. 8 — Apr. 11, 2011
  • pp: 7625–7632

Wavelength-selective directional couplers as ultrafast optical differentiators

Tae-Jung Ahn and José Azaña  »View Author Affiliations

Optics Express, Vol. 19, Issue 8, pp. 7625-7632 (2011)

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Wavelength-selective directional couplers with dissimilar waveguides are designed for ultrafast optical differentiation within the femtosecond regime (corresponding to processing bandwidths > 10 THz). The theoretically proposed coupler-based differentiators can be produced by wavelength matching of the propagation constants of two different waveguides in the coupler at the center wavelength. A single directional coupler can be designed to achieve either a 2nd-order differentiator or a 1st-order differentiator by properly fixing the product of coupling coefficient and coupling length of the coupler. We evaluated the differentiation errors (~2%) and energetic efficiency (~11% for 1st order differentiation) of the designed optical differentiators through numerical simulations. The proposed design has a strong potential to provide a feasible solution as an integrated differentiation unit device for ultrafast optical signal processing circuits.

© 2011 OSA

OCIS Codes
(320.5540) Ultrafast optics : Pulse shaping
(320.7080) Ultrafast optics : Ultrafast devices
(320.7085) Ultrafast optics : Ultrafast information processing

ToC Category:
Ultrafast Optics

Original Manuscript: January 21, 2011
Revised Manuscript: February 23, 2011
Manuscript Accepted: March 25, 2011
Published: April 6, 2011

Tae-Jung Ahn and José Azaña, "Wavelength-selective directional couplers as ultrafast optical differentiators," Opt. Express 19, 7625-7632 (2011)

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