Structural Transition Expansion of Photonic Band Gap for a Nonlinear One Dimensional Photonic Crystal

Photonic crystals are periodic optical nanostructures that can control the flow of light. A theoretical design of a one dimensional dielectric/semiconductor (Zinc Selenide /Gallium) nonlinear omnideirectional photonic crystal is proposed for multiphotonic band gap device. Investigation of 30 layers one dimensional photonic crystal, where Zinc Selenide and Gallium are respectively a low refractive index material (n(proportional to)) and a high refractive index material (n(beta)). The refractive index of both the materials nonlinearly depends on the intensity and wavelength; both materials are nonlinear optical materials. The proposed quarter wave stack structure is investigated in the form air (n(proportional to), n(beta))(30)air. Reflectivity and Transmissivity for these structures at normal incidence has been calculated by using transfer matrix method. The results show that if the incident wavelength in the visible region then by varying the critical wavelength of controlling wave, the complete Omnidirectional photonic band gap varies due to structural transition that means a single device can be used as multi omnidirectional photonic band gap. Such kind of devices may be useful to understand natural photonic crystals. This device may be used as optical and photonic applications such as optical filters, optical light modulators, optical smart windows, optical sensors and optical logic gates etc., where multi omnidirectional photonic band gap can be used.