Enlargement of Photonic Band Gap in Porous Silicon Dielectric Mirrors

Abstract

In this work, we demonstrate that a series of one-dimensional photonic crystal structures of low index-contrast can exhibit complete reflection for all the visible range. The dielectric reflector consists of a combination of three porous silicon mirrors of the same refractive index contrast, but of different periods. We present a simple manner to increase the width of the photonic band gap, as large as desired, to construct a photonic heterostructure with perfect light reflection in the visible range using a minimum number of periods. We also study the role of the absorption on the optical properties of the heterostructure mirror.