文摘
We propose and demonstrate theoretically omnidirectional and controllable switching behavior by combining the advantages of the controllable properties of a photonic quantum well system and the omnidirectional resonant defect modes of single-negative material heterostructures. Our numerical results reveal that the frequency positions of strong localized states are different for odd numbers and even numbers of wells, which can be used to design an all-optical switch by adding or reducing one well. Furthermore, the frequency position can be adjusted by modifying the width of the wells. Compared to conventional all-optical switches, the frequency position of the proposed switch is not only adjustable, but it is also insensitive to the incidence angle of light. The proposed method thus provides a simple way of designing an omnidirectional and controllable all-optical switch.