Structural design of a broadband spiral nanoantenna for solar energy collection

Abstract

In this research, a new design of spiral nanoantenna for solar energy harvesting was proposed and analyzed by using three-dimensional finite difference time-domain method. The structure of the proposed nanoantenna consisted of two Archimedean spiral arms integrated on a supporting substrate layer. The analysis included the radiation efficiencies, polarization, near-field characteristics and far-field patterns. The new nanoantenna considers the polarized characteristics of sunlight and has high total radiation efficiency of 74.49% within the broad wavelength range from 400 to 1600 nm, which are both superior to those of previously proposed linear antennas. Moreover, the same order of electric enhancement factor at the spiral gap was also obtained for different linearly polarized incident waves. Furthermore, the far-field characteristics of the proposed nanoantenna were studied for wide-angle reception.