Open Access Original paper

Analysis of optical absorption in GaAs nanowire arrays

Haomin Guo, Long Wen, Xinhua Li*, Zhifei Zhao and Yuqi Wang

Author Affiliations

Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031, People's Republic of China

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Nanoscale Research Letters 2011, 6:617  doi:10.1186/1556-276X-6-617

Published: 6 December 2011

Abstract

In this study, the influence of the geometric parameters on the optical absorption of gallium arsenide [GaAs] nanowire arrays [NWAs] has been systematically analyzed using finite-difference time-domain simulations. The calculations reveal that the optical absorption is sensitive to the geometric parameters such as diameter [D], length [L], and filling ratio [D/P], and more efficient light absorption can be obtained in GaAs NWAs than in thin films with the same thickness due to the combined effects of intrinsic antireflection and efficient excitation of resonant modes. Optimized geometric parameters are obtained as follows: D = 180 nm, L = 2 μm, and D/P = 0.5. Meanwhile, the simulation on the absorption of GaAs NWAs for oblique incidence has also been carried out. The underlying physics is discussed in this work.

PACS: 81.07.Gf nanowires; 81.05.Ea III-V semiconductors; 88.40.hj efficiency and performance of solar cells; 73.50.Pz photoconduction and photovoltaic effects.