; Compute the bands at the X point for a quarter-wave stack Bragg ; mirror (this is the point that defines the band gap edges). ; the high and low indices: (define-param n-lo 1.0) (define-param n-hi 3.0) (define-param w-hi (/ n-lo (+ n-hi n-lo))) ; a quarter-wave stack (set! geometry-lattice (make lattice (size 1 no-size no-size))) ; 1d cell (set! default-material (make dielectric (index n-lo))) (set! geometry (list (make cylinder (material (make dielectric (index n-hi))) (center 0 0 0) (axis 1 0 0) (radius infinity) (height w-hi)))) (define-param kx 0.5) (set! k-points (list (vector3 kx 0 0))) (set-param! resolution 32) (set-param! num-bands 8) (run-tm) ; note that TM and TE bands are degenerate, so we only need TM
