摘要 : It is shown that a layer of low refractive index, sandwiched between two multilayer stacks made from commonly used dielectric materials, can be designed to be completely free of all modes within a band of frequencies, i.e., to sup... 展开 It is shown that a layer of low refractive index, sandwiched between two multilayer stacks made from commonly used dielectric materials, can be designed to be completely free of all modes within a band of frequencies, i.e., to support a species of full photonic bandgap. In a slightly thicker layer, only one mode is supported. For in-plane electric field polarization and a radiating dipole placed in the centre of the layer, the spontaneous emission coupling ratio is βSE = 0.96, very high for such a simple structure. 收起