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Energy Express

Energy Express

  • Editor: Christian Seassal
  • Vol. 22, Iss. S2 — Mar. 10, 2014
  • pp: A225–A232

Enhanced photocarrier generation in large-scale photonic nanostructures fabricated from vertically aligned quantum dots

Takeshi Tayagaki, Yusuke Hoshi, Yuko Kishimoto, and Noritaka Usami  »View Author Affiliations

Optics Express, Vol. 22, Issue S2, pp. A225-A232 (2014)

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We demonstrate enhanced photocarrier generation using photonic nanostructures fabricated by a wet etching technique with vertically aligned quantum dots (QDs). Using photoluminescence excitation spectroscopy, we found that the photocarrier generation in Ge/Si QDs placed close to the surface is enhanced below the band gap energy of crystalline silicon. The enhancement is explained by light trapping owing to the photonic nanostructures. Electromagnetic wave simulations indicate that the photonic nanostructure with a subwavelength size will be available to light trapping for efficient photocarrier generation by increasing their dip depth.

© 2014 Optical Society of America

OCIS Codes
(350.6050) Other areas of optics : Solar energy
(160.4236) Materials : Nanomaterials
(310.6628) Thin films : Subwavelength structures, nanostructures

ToC Category:
Light Trapping for Photovoltaics

Original Manuscript: November 29, 2013
Revised Manuscript: January 10, 2014
Manuscript Accepted: January 13, 2014
Published: January 22, 2014

Takeshi Tayagaki, Yusuke Hoshi, Yuko Kishimoto, and Noritaka Usami, "Enhanced photocarrier generation in large-scale photonic nanostructures fabricated from vertically aligned quantum dots," Opt. Express 22, A225-A232 (2014)

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