次波长光学成像的理论研究

The performance of a conventional optical lens is restricted by diffraction limit: no lens can focus light onto an area smaller than a square wavelength. Consequently, the components of the image point are not complete compared to those of the source point. Motivated by this reason, a novel, interesting and challenging subject comes into being, on finding new materials on subwavelength imaging, establishing the corresponding imaging theory, and breaking the conventional diffraction limit. In this proposal, we plan to seek new artifical eletromagnetic structures, develop the existing theory on subwavelength imaging and realize broadband, long-distrance subwavelength image transfer, which is also not sensitive to source polarization. The detail content is as follows: (1) We propose two-dimensional and three-dimensional electromagnetic structure, i.e. dielectric photonic crystals, metallic plasmonic crystals or metal-dielectric multilayers, and realize long-distance subwavelength image transfer by using the concept of one-way protected edge states; (2) In order to reduce the impact of material loss, we design stacked layers of superconducting nanorod array or holey superconducting structures, and realize the far-field, broadband subwavelength imaging; (3) We use the oblique metal-dielectric multilayers, realize and manipulate the subwavelength imaging, insensitive of source polarization; (4) Finally, for the medical imaging, we predict to set up the endoscope, with super-resolution, flexible, long-distance color imaging transfer.

传统的光学透镜受衍射极限的限制，小于光波长尺寸的区域无法通过透镜聚焦，最终所成像点的信息不够全面。因此，寻找新型的透镜材质，建立次波长光学成像理论，突破传统的光学衍射极限，成为最近一个有趣，且富有挑战性的全新课题。本项目拟理论设计新的人工电磁结构，发展目前的次波长成像理论，实现对源极化不敏感、宽频、远场的次波长成像。具体内容包括：（1）设计二维及三维周期性电磁材料结构，如介电光子晶体，金属等离子晶体或多层金属-电介质结构，结合单方向边缘保护态的概念，实现远场长程的次波长成像；（2）拟结合高温超导材料，减少材料损耗的影响，设计多层超导纳米棒阵列及多孔超导结构，实现远场、宽频的次波长成像；（3）设计倾斜的多层电磁结构，实现并调控源极化不敏感的次波长图像（4）最终理论设计可自由弯曲的、长程传输图像的具有高分辨率的内窥镜装置，用于医学成像等领域。

传统的光学透镜受衍射极限的限制，小于光波长尺寸的区域无法通过透镜聚焦，最终所成像的信息不够全面。本项目理论设计了新的人工电磁结构，发展目前的次波长理论，实现了磁场可控， 远场，长程的次波长成像。主要研究内容如下：（1）设计了涡旋状层结构的双曲型超级透镜，灵活地控制传输次波长图像；(2) 设计了磁性双曲型超级透镜，实现磁场可控、长程传输次波长图像；(3) 研究光学超晶格表面塔姆态及其单向传输性质，应用于次波长成像；(4) 研究了具有宇称-时间对称的磁畴结构中等效磁导率接近于零的非互易电磁模式，以应用于次波长成像；(5) 研究了磁化的双原子等离子链的非互易能带分布，以应用于设计磁场可控的次波长成像。本项目的完成将有助于设计自由弯曲，灵活可控，长程传输图像，具有高分辨率的内窥镜装置，用于医学成像等领域。