PWE_PBS_3Dbcc

代码说明：

  Calculates photonic band structure for either the bcc lattice of dielectric spheres of dielectric constant epsilon_a in a dielectric background of dielectric constant epsilon_b.(Calculates photonic band structure for ei ther'isnt the bcc lattice of dielectric spheres of di electric constant epsilon_a in a dielectric ba ckground epsilon_b of dielectric constant.)