将电磁场的能量压缩在一个亚波长尺寸的空气区域中，可在诸多场合有应用价值，比如超分辨成像、微弱信号探测、高精度电磁加工/操控、电磁传感器灵敏度增强等。本研究中，我们提出一种在零折射率介质中参杂的方法来在一个亚波长空气区域中获得高倍率的电场增强与电磁波能量增强，可以用于对传感器灵敏度的改善。

研究亮点：

1）高均匀度增强。

2）深亚波长空气区域内增强。

3）宽带增强。

4）增强因子可调节。

Confining electric field in the sub-wavelength region has various applications, such as super-resolution imaging, detecting extremely weak electromagnetic signal, quantum computing, and sub-wavelength electromagnetic/biological manipulation/sensing. In this study, we design a novel electric compressor by doping a metallic-air-metallic pillar in epsilon-near-zero medium, which can confine/capture electric field in a 3D deep sub-wavelength air pillar with high uniformity. 

The proposed electric field compressor is designed by introducing a metal-air-metal pillar into an epsilon-near-zero medium within a metallic waveguide. A practical model is proposed for the implementation of the electric field compressor in the microwave range. The novelty and advantages of the proposed compressor can be summarized as:

1) The compressor is capable of achieving a tunable electric field enhancement effect within a deep sub-wavelength air pillar. This is accomplished by adjusting the height of the air pillar through the movement of two metal pillars inserted into the waveguide.

2)The proposed compressor can provide a broad range of tunable field enhancement effects, allowing the enhancement factor to be continuously adjustable between 20 and 800.

3) The enhanced electric field in the air pillar is uniform, i.e., the field enhancement exhibits a high level of uniformity. 

4)The enhanced electric field is within a 3D deep sub-wavelength air pillar, where the air volume is smaller than  λ0/15  λ0/15  λ0/34.

专利投寄：CN202310565834.6.

论文发表： Fei Sun, Jinyuan Shan, Yichao Liu*, and Xiaodan Zhao “Tunable uniform field enhancement in a subwavelength air pillar by photonic doping in epsilon-near-zero medium,” Results in Physics 61, 107778 (2024).