Broadband visible light absorber based on ultrathin semiconductor nanostructures

• 来源期刊: 中国物理B（英文版）
• 关键词: ultrathin nanostructures electrical resonance magnetic resonance polarization insensitivity
• 年，卷（期）: 2020,（1）
• 页码范围: 289-295
• 页数: 7页
• 语种: 英文
• DOI: 10.1088/1674-1056/ab5787

摘要

It is desirable to have electromagnetic wave absorbers with ultrathin structural thickness and broader spectral absorp-tion bandwidth with numerous applications in optoelectronics . In this paper, we theoretically propose and numerically demonstrate a novel ultrathin nanostructure absorber composed of semiconductor nanoring array and a uniform gold sub-strate. The results show that the absorption covers the entire visible light region, achieving an average absorption rate more than 90％in a wavelength range from 300 nm to 740 nm and a nearly perfect absorption from 450 nm to 500 nm, and the polarization insensitivity performance is particularly great. The absorption performance is mainly caused by the electrical resonance and magnetic resonance of semiconductor nanoring array as well as the field coupling effects. Our designed broadband visible light absorber has wide application prospects in the fields of thermal photovoltaics and photodetectors.