摘要
针对二维硅光栅微结构在近红外光吸收率极低的特点,提出了一种利用等离激元增强金属Ag纳米凹坑-硅栅近红外光吸收的微纳组合结构,基于时域有限差分法研究了该组合结构在0.78~2.5μm宽波段的吸收率,分析了光栅结构与Ag纳米凹坑对光吸收效率的影响变化。模拟研究结果表明,当在周期为0.2μm、占空比为0.5的光栅间隙和栅柱表面均嵌入直径为0.1μm的Ag纳米凹坑时,该组合微结构在近红外宽波段吸收率均在23%以上,平均吸收率理论上可达到52.3%;当光栅表面增加Al;O;介质层时,宽波段吸收率均在41.3%以上,平均吸收率提高到65.1%,最终在近红外宽波长范围内提高了吸收效率。该研究为光电探测器、太阳能电池、光通信、雷达隐身、生物医疗等领域增强光吸收提供了一种新的方法。
Aiming at the characteristics of two-dimensional silicon grating microstructure in the near infrared light absorption rate is extremely low,a micro-nano composite structure is proposed to enhance the near infrared absorption of Ag nano-pit and silicon grating by using isolators.The absorption rate of the composite structure in the wavelength range from 0.78μm to 2.5μm is studied based on the finite-difference time-domain method.The influence of the grating structure and Ag nano-pits on the light absorption efficiency is analyzed.The simulation results show that when Ag nano pits with a diameter of 0.1μm are embedded in the grating gap with a period of 0.2μm and a duty cycle of 0.5 and on the surface of the grid column,the absorptivity of the composite microstructure is above 23%in the near infrared wide band,and the average absorptivity is up to 52.3%,theoretically.When Al;O;dielectric layer is added on the grating surface,the absorption rate of wide band is above 41.3%,and the average absorption rate is increased to 65.1%.Finally,the absorption efficiency is improved in the wide wavelength range of near infrared,which provides a new method to enhance optical absorption in photodetector,solar cell,optical communication,radar stealth,biomedical and so on.
作者
孙国斌
张锦
蒋世磊
杨柳
Sun Guobin;Zhang Jin;Jiang Shilei;Yang Liu(School of Optoelectronic Engineering,Xi’an Technological University,Xi’an,Shaanxi 710021,China)
出处
《激光与光电子学进展》
CSCD
北大核心
2022年第5期288-295,共8页
Laser & Optoelectronics Progress
基金
陕西省教育厅重点实验室科研计划(18JS053)
陕西省科技厅重点实验室项目(2013SZS14-P01)。
关键词
光栅
光吸收增强
Ag纳米凹坑
硅光栅结构
等离激元
gratings
enhanced optical absorption
Ag nano-pit
silicon grating structure
plasmon polariton
