Ultra-broadband reflector using double-layer subwavelength gratings

• 作者: HONGFEI JIAO JINLONG ZHANG SHUAIKAI SHI XIAOCHUAN JI XINBIN CHENG ZHANSHAN WANG
• 来源期刊: 光子学研究:英文版
• 学科: 工学
• 关键词: LITHOGRAPHY LAYER reflectance
• 年，卷（期）: 2020,（3）
• 页码范围: 426-429
• 页数: 4页
• 分类号: TN2

摘要

Double-layer high-contrast subwavelength gratings that are separated by a dielectric space layer are investigated to achieve ultra-broadband reflection.The reflection phase of subwavelength gratings and the propagation phase shift between two gratings are manipulated to expand reflection bandwidth by properly stacking two reflective gratings.A reflector exhibiting a 99%reflectance bandwidth of~1080 nm in the near-infrared is designed.Then this reflector is prepared using laser interference lithography and ion beam planarization,and an ultra-broadband reflection is achieved with reflectance exceeding 97%over a wavelength range of 955 nm in the near-infrared region.