Optimization and fabrication of the photonic crystals for large absolute band gaps

In the paper, Optimization algorithm is used to design two-dimensional photonic crystals for large absolute band gaps. By optimizing the location and radius of rods in the unit cell, we present tree designs considering different shape rods. The genetic algorithm finally yielded a photonic crystal with an absolute common band gap of 0.0796(2πc/a) at the mid-frequency of 0.3712(2πc/a). The result have been fabricated using e-beam lithography (EBL) and inductively coupled plasma (ICP). We can find a large absolute band gap can be obtained.