A polarization-insensitive fishnet/spacer/mirror plasmonic absorber for hot electron photodetection application

• 来源期刊: 中国光学快报（英文版）
• 年，卷（期）: 2020,（5）
• 页码范围: 63-67
• 页数: 5页
• 语种: 英文
• DOI: 10.3788/COL202018.052402

摘要

A polarization-insensitive plasmonic absorber is designed consisting of Au fishnet structures on a TiO2 spacer/Ag mirror.The fishnet structures excite localized surface plasmon and generate hot electrons from the absorbed photons,while the TiO2 layer induces Fabry-Perot resonance,and the Ag mirror acts as a back reflector.Through optimizing the TiO2 layer thickness,numerical simulation shows that 97％ of the incident light is absorbed in the Au layer.The maximum responsivity and external quantum efficiency of the device can approach 5 mA/W and ～1％,respectively,at the wavelength of 700 nm.