Equivalent circuit, enhanced light transmission and power flow through subwavelength nanoslit of silver and gold and surrounding medium

The concept of an equivalent circuit is a simple and effective method for studying the role of plasmonic and non-plasmonic nano-objects in nanodevices. This work discusses an equivalent circuit and optical properties for nanoslit and its surrounding medium. Based on the characteristic impedance approach, a new model was designed for an equivalent circuit of nanoslit. To control the amount of electric field and power flow, a novel idea of silver-gold nanoslit is presented. Its results are compared with silver-silver nanoslit and gold–gold nanoslit. The results of this study show that the response of the nanoslit can be tailored by optimizing the parameters, including the refractive index of the surrounding medium, permittivity and permeability of the materials and subwavelength parameters of the nanoslit. Using this approach, it would be possible to design complex equivalent circuits in the future for nanodevices.