Tungsten Supported Plasmonic Nanoscale Absorber for Solar Thermal Photovoltaics Applications

Abstract

Current and modern photovoltaics energy systems require miniaturized, ultrathin, compact and high efficiency absorbing and optical devices. So, by keeping these challenges in mind and inspired by the artificially engineered materials, called metamaterials, a high bandwidth optical nanostructured based absorbing device is presented in this report. The design geometry of the proposed nano-absorber comprises an array of nano-circular antennas, etched on a dielectric spacer, aluminium nitride (AlN) which is coated by a thick reflecting layer of silver from the backside. Surprisingly, the design absorber offers high absorption value of above 90% across the large operational wavelengths starting from 400 to 1500 nm. The constituting nano-antennas induces plasmonic resonance features, which enables the localized surface plasmon and results in an enhanced absorption. The nanoscale absorber is also investigated under the excitation of polarization and oblique incident angles of the incoming optical light. Finally, the plasmonic metal, tungsten (W) offers high melting point so that it can sustain under the high-energy photon particles. As compared to previous published work related to plasmonic absorbers, this work provide ultra-compact geometry, easily manufactured design, super bandwidth and polarization insensitivity. So, this can be used for the applications of thermophotovoltaics and energy harvesting etc.