Wen Feng, David Sylvain, Checoury Xavier, El Kurdi Moustafa, Boucaud Philippe
Institut d'Electronique Fondamentale, Bât. 220 CNRS-Univ Paris Sud 91405 Orsay, France.
Opt Express. 2008 Aug 4;16(16):12278-89. doi: 10.1364/oe.16.012278.
Photonic crystals exhibiting a photonic band gap in both TE and TM polarizations are particularly interesting for a better control of light confinement. The simultaneous achievement of large band gaps in both polarizations requires to reduce the symmetry properties of the photonic crystal lattice. In this letter, we propose two different designs of two-dimensional photonic crystals patterned in high refractive index thin silicon slabs. These slabs are known to limit the opening of photonic band gaps for both polarizations. The proposed designs exhibit large complete photonic band gaps: the first photonic crystal structure is based on the honey-comb lattice with two different hole radii and the second structure is based on a "tri-ellipse" pattern in a triangular lattice. Photonic band gap calculations show that these structures offer large complete photonic band gaps deltaomega/omega larger than 10% between first and second photonic bands. This figure of merit is obtained with single-mode slab waveguides and is not restricted to modes below light cone.
在TE和TM偏振中均表现出光子带隙的光子晶体对于更好地控制光限制特别有趣。要在两种偏振中同时实现大的带隙，需要降低光子晶体晶格的对称性。在本信函中，我们提出了两种不同的二维光子晶体设计，它们图案化在高折射率薄硅平板中。已知这些平板会限制两种偏振的光子带隙的开口。所提出的设计展示出大的完全光子带隙：第一种光子晶体结构基于具有两种不同孔半径的蜂窝晶格，第二种结构基于三角晶格中的“三椭圆”图案。光子带隙计算表明，这些结构在第一和第二光子带之间提供大于10%的大的完全光子带隙Δω/ω。这个品质因数是通过单模平板波导获得的，并且不限于光锥以下的模式。
