Omnidirectional reflection from Fibonacci quasi-periodic one-dimensional photonic crystal

It is shown that omnidirectional reflection (ODR) is possible from quasi-periodic isotropic dielectric stacks following a Fibonacci sequence (FS). The transition from truly periodic to fully quasi-periodic structure is investigated by building periodic structures having unit cells made of FS of order j. The number of periods required to achieve ODR decreases as j increases until only a single period is required at which the structure is fully quasi-periodic. As compared to the periodic case, for the quasi-periodic structure the spectral range is wider, the thickness of the single layers is smaller and the tolerance on the layer thicknesses is smaller.