SiO2/bi-layer GZO/Ag structures for near-infrared broadband wide-angle perfect absorption

In this work, near-infrared (NIR) perfect absorbers with a silicon dioxide (SiO2)/gallium-doped zinc oxide (GZO)/silver (Ag) multi-layer structure were designed and experimentally demonstrated. The results show that a broadband perfect absorption (PA) from 1.24 mu m to 1.49 mu m was achieved by adopting bi-layer GZO thin films with different carrier concentrations. This absorption remained higher than 97% for incident angles up to 60 degrees. The perfect NIR absorber reported here has a simple structure as well as broadband and wide-angle absorption features, which is promising for practical applications.