Fabrication of Linear Polarization-Separating Silicon Metalens at Long-Wavelength Infrared
Fabrication of Linear Polarization-Separating Silicon Metalens at Long-Wavelength Infrared
复制标题
长波红外线偏振分离硅超透镜的制备
DOI：
10.1007/978-3-031-29871-4_15
复制
发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Iwami Kentaro
中科院分区：
文献类型：
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作者：
Ishizuka Noe;Li Jie;Fuji Wataru;Ikezawa Satoshi;Iwami Kentaro
设计、研制并演示了一种长波长红外偏振分离金属透镜。两种高透过率的正交线偏振均采用硅四角柱作为准原子，在10.6πm的设计波长下实现了2μ的全相位覆盖。通过基于有限元方法的电磁场分析确定了它们的尺寸，所有金属原子的透过率都在70%以上。采用电子束光刻和反应离子刻蚀的方法制备了金属透镜，扫描电子显微镜观察表明，金属透镜的制备过程中保持了良好的垂直度。使用市售的微测辐射热计进行了成像测试，并确认光在每个线偏振的不同位置聚焦。在45°偏振照明的情况下，证实了光在两个位置都聚焦了。所制备的金属透镜成功地展示了热图像的线偏振分离能力。
A polarization-separating metalens at the long-wavelength infrared was designed, developed, and demonstrated. The silicon quadrangular pillars are adopted as meta-atoms to achieve full 2π phase coverage at the design wavelength of 10.6 μm for both of two orthogonal linear polarizations with high transmittance. Their dimensions were determined by electromagnetic field analysis based on a finite element method, and transmittances of more than 70% were obtained in all meta-atoms. The metalens was fabricated through electron beam lithography and reactive ion etching, and SEM observation showed that the fabrication was done while maintaining good verticality. An imaging test was performed using a commercially available micro-bolometer, and it was confirmed that the light was focused at different positions for each linear polarization. In the case of 45°-polarized illumination, it was confirmed that the light was focused at both locations. The fabricated metalens successfully showed the ability of linear polarization separation of a thermal image.