Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1539135 | Optics Communications | 2009 | 6 Pages |
A genetic algorithm (GA) is used for the design of two-dimensional photonic crystals with large stop-bands. In this procedure, the unit cell of the crystal with square lattice is assumed to be composed of a number of Si round rods. And the key point to obtain maximum absolute band-gap is using the GA to optimize the radius and center position of each rod in unit cell. In the implementations of GA, the structure of each unit cell is represented by a binary string and the fitness (the absolute band-gap) for each unit cell is calculated by the plane-wave expansion (PWE) method. As numerical examples, we present several GA designs considering different number of round rods in the unit cell as well as the band-gap under the light line. The maximum absolute bandwidth of these optimized band-gaps is 0.1466(2πc/a)0.1466(2πc/a).