Field enhancement in a photonic band gap cavity assisted by metal grooves

In this paper we explore the possibility to accomplish field enhancement in the visible range in a photonic band gap cavity inserted in a Bragg waveguide, assisted by a silver metal groove. The investigation we carried out shows how the resonant mode can be localized in dielectric region under a Bragg grating; a thorough evaluation of some characteristic parameters also allows to determine whether the plasmons originating at the metal-dielectric interface actually play a key role in the field localization and enhancement phenomenon. The analysis has been performed by using the FDTD method, where the actual data of the Ag permittivity are introduced by means of the Drude model. This application can represent an alternative fashion of tuning and enhancing the resonant mode for novel LED applications.