Measurement and modelization of silica opal reflection properties: Optical determination of the silica index

作者:Avoine Amaury*; Phan Ngoc Hong; Frederich Hugo; Frigerio Jean Marc; Coolen Laurent; Schwob Catherine; Pham Thu Nga; Gallas Bruno; Maitre Agnes
来源:Physical Review B, 2012, 86(16): 165432.
DOI:10.1103/PhysRevB.86.165432

摘要

Self-assembled artificial opals (in particular silica opals) constitute a model system to study the optical properties of three-dimensional photonic crystals. The silica optical index is a key parameter to correctly describe an opal but is difficult to measure at the submicrometer scale and usually treated as a free parameter. Here, we propose a method to extract the silica index from the opal reflection spectra and we validate it by comparison with two independent methods based on infrared measurements. We show that this index gives a correct description of the opal reflection spectra, either by a band structure or by a Bragg approximation. In particular, we are able to provide explanations in quantitative agreement with the measurements for two features : the observation of a second reflection peak in specular direction, and the quasicollapse of the p-polarized main reflection peak at a typical angle of 54 degrees.

  • 出版日期2012-10-19