受限原子蒸气/电介质周期层状结构中光子带隙的厚度调制

周期性受限原子蒸气/电介质层光子带隙(PBG)宽度及其诱导的反射平顶随蒸气层厚度d的增大而变宽,并在d/(λ0/2)=0.5(λ0为原子的共振波长)时达到最大值,之后随d的增大呈变窄趋势.随着蒸气厚度的增大,带隙的中心频率产生红移,厚度越大,红移量越大.研究还发现,共振波长处的反射及透射谱具有迪克窄化结构.这种可调谐的PBGs结构可望用于全光反射镜及滤波器.

Thickness modification on photonic band gap in periodic layers of confined atomic vapor/dielectric medium

The width of photonic band gap (PBG) and the gap induced reflectance flat-top in periodic layers of confined atomic vapor/dielectric medium are broadened as the vapor thickness d increases, and approach to a maximum value at (where is the atomic resonant wavelength), and then, they are narrowed again as d increases. The gap center frequency is red-shifted as the vapor thickness increases, the larger the vapor thickness, the greater the shifted amount. Dicke-narrowing reflection and absorption lines are also exhibited at resonant wavelength. These tunable PBGs can be probably used in the applications of all-optical reflectance mirrors and filters.