Optical logic gates play important roles in all-optical logic circuits, which lie at the heart of the next-generation optical computing technology. However, the intrinsic contradiction between compactness and robustness hinders the development in this field. Here, we propose a simple design principle that can possess multiple-input-output states according to the incident circular polarization and direction based on the metasurface doublet, which enables controlled-NOT logic gates in infrared region. Therefore, the directional asymmetric electromagnetic transmission can be achieved. As a proof of concept, a spin-dependent Janus metasurface is designed and experimentally verified that four distinct images corresponding to four input states can be captured in the far-field. In addition, since the design method is derived from geometric optics, it can be easily applied to other spectra. We believe that the proposed metasurface doublet may empower many potential applications in chiral imaging, chiroptical spectroscopy and optical computing.

为了减小不同光谱辐射计间瞄准区域差异带来的光谱辐射亮度不一致性，讨论了视场角及定位对于测量准确性的影响。通过建立太阳光白板和卤钨灯白板系统光路下的光谱辐射亮度测量模型，分析了不同几何光路视场区域平均辐射亮度与中心辐射亮度的差异。数值模拟表明，太阳光白板光路修正因子仅与视场角大小有关；卤钨灯白板光路修正因子随测量距离增大而减小，距离600 mm时8°和14°视场角的修正因子分别变为0.993 5和0.980 2。最后，实验验证了卤钨灯白板系统下角度误差和位移误差对光谱辐射亮度的影响。结果表明，修正因子对水平方向的角度误差和位移误差呈现非对称性，两侧差异高达2%。因此，依据视场角和几何定位可以对测量结果进行数据修正，有助于提升光谱辐射亮度测量不确定度水平。

钍基熔盐堆10 MW固态实验堆设计采用活化法测量反应堆内部中子能谱分布，中子活化样品在堆外装载后通过传输装置将其快速输送到堆内测量位置进行辐照，辐照完后将其输出到能谱样品间进行解谱分析，进而获取堆内能谱分布情况。为实现中子能谱样品快速进出反应堆，设计了一种堆内双层套管中子活化样品气力输送系统，采用Fluent仿真方法研究样品在不同管道间隙下的运动规律。采用气力输送理论对原理样机的流量、两相流压损等工作参数进行设计并对原理样机的结果进行对比验证试验。试验结果表明：样品运动速度、气体流量和压损等测量参数与理论设计值符合较好，设计方法可行，双层套管的结构设计可以实现样品顺畅进出堆芯的功能。