DBR stack structure
dbr_stack(lambda0 = 630, n1 = 1.28, n2 = 1.72, d1 = lambda0/4/n1, d2 = lambda0/4/n2, N = 2 * pairs, pairs = 4, ...)
list of class 'stack'
periodic structure of dielectric layers
Other stack user_level: embed_stack,
layer_stack, tamm_stack_ir,
tamm_stack_porous, tamm_stack