期刊
INFOMAT
卷 4, 期 2, 页码 -出版社
WILEY
DOI: 10.1002/inf2.12264
关键词
all-dielectric metamaterials; beam steering; mid-infrared; on-chip focusing; photonic integrated circuits
资金
- Advanced Research and Technology Innovation Centre
- A*STAR [A18A5b0056]
- National Research Foundation-Singapore [NRF-CRP15-2015-02, RIE2020-AME-2019]
- National University of Singapore [R261-518-009-720]
Photonic integrated circuits (PICs) offer a promising platform for miniaturized on-chip optical systems, with one key aspect being the dense integration of photonic components. This study introduces a bigradient on-chip metalens (BOML) to achieve ultrasmall focal lengths and spot sizes at the subwavelength scale for efficient on-chip focusing in PICs. The BOML design combines gradient geometry and refractive index to optimize performance metrics such as figure-of-merits and numerical aperture, enabling high-density on-chip photonic systems for various applications.
Photonic integrated circuits (PICs) provide a promising platform for miniaturized on-chip optical systems for communication, computation, and sensing applications. The dense integration of photonic components is one of the keys to exploit the advantages of PIC. Although light focusing is a fundamental and indispensable function in PICs, focusing light at the micro/nanometer-scale is challenging. Here, a bigradient on-chip metalens (BOML) is proposed to achieve ultrasmall focal lengths and spot sizes at the subwavelength scale for dense PICs. The design of BOML combines gradient geometry and gradient refractive index into one metalens by simultaneously engineering the length and width of subwavelength silicon slots. With a small device footprint of only 168 mu m, the BOML achieves efficient on-chip focusing with the record-breaking figure-of-merits, which are the ratio of wavelength to focal length/spot size (0.268 and 2.83) and numerical aperture (1.78). Leveraging on the Fresnel design, the footprint of BOML is further reduced by 55.1%, and the numerical aperture is enhanced to 1.9. The demonstration of mode conversion and beam steering with efficiency over 80% and a tilting range of 7.2 degrees holds the potential for highly dense on-chip photonic systems for optical communication, optical sensing, nonlinear optics, and neural networks for deep learning.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据