Design and optimization of slot nano-antennas for ambient thermal energy harvesting

This paper reports the design and analysis of three proposed slot nano-antennas for infrared energy collection at 30 THz. Since Slot nano-antennas have sharp edge design, they have the ability to confine electromagnetic fields very strongly in subwavelength scale. In this study, we have investigated the influence of slot nano-antenna parameters on its response such as bandwidth, peak gain, and half-power beamwidth. To characterize the performance of each nano-antenna, a figure of merit (FOM) has been proposed and calculated. Three antennas under investigation are: slot dipole, slot crossed dipole, and slot bow-tie nano-antennas. According to the proposed FOM, the slot bow-tie exhibits superior performance among the three slot nano-antennas and previously reported configurations. This work, to the authors' knowledge, is the first investigation about the slot nano-antennas for thermal energy harvesting applications at 30 THz.