磁控纳米冷阴极太赫兹辐射源器件物理及关键技术研究

Vacuum electron Terahertz(THz) radiation sources, as one of important driving forces of development THz Science and technology, have been attracted much attention. However, the application of thermionic cathode has many limitations in vacuum electron THz radiation sources, because the device’s size decreases with the increase of frequency of THz radiation source. Field emission nano cold cathode is not limited by the size of structure, and have inherent advantages in the application of vacuum electron THz radiation source. However, field emission electrons are easy to bombard the anode. It is difficult to form an electron beam and limits the application of nano cold cathode. In this project, magnetically conrolled nano cold cathode THz radiation sources will be investigated based on above issues. The key technology of miniature electron optical system of THz radiation source will be obtained based on advantages of nano cold cathode and crossed electric and magnetic fields on the surface of cold cathode. Through inputing microwave/millimeter-wave in the electron optical system, the premodulation field emission electron beam will be formed and the beam-wave interaction physical mechanism will be anlaysed. The key technology of THz raditaion generated in a micro-interaction-cavity will be obtained. Finally, technologies of development of nano cold cathode vacuum electron THz radiation source devices will be masterd. THz science and technology further rapid aplication in the field of national security, space science,communications technology, will be promoted.

真空电子太赫兹辐射源作为太赫兹科学技术发展的重要推力之一一直备受关注。但随着辐射源频率的升高，器件尺寸逐渐减小，热阴极在其中的应用面临诸多限制。场致发射纳米冷阴极不受结构尺寸限制，应用于真空电子太赫兹辐射源中具有先天优势，但场致发射电子极易轰击阳极，电子注难于成形，导致纳米冷阴极应用受限。本项目基于此对磁控纳米冷阴极太赫兹辐射源开展研究。采用在阴极区施加正交的电场和磁场以产生电子注，再结合纳米冷阴极尺寸小，外形可塑性高等特点解决真空电子太赫兹辐射源中电子光学系统小型化的关键技术。采用微波毫米波对纳米冷阴极场致发射过程进行直接调制，探析场发射调制电子注与高频场互作用物理过程，解决真空电子太赫兹辐射源中微小空间下的有效注波互作用关键技术。最终掌握研制纳米冷阴极太赫兹辐射源的核心技术，推动真空电子太赫兹辐射源快速发展，为纳米太赫兹科学技术在国家安全、空天技术、通信技术等领域的进一步应用奠定基础。

真空电子太赫兹辐射源作为太赫兹科学技术发展的重要推力之一一直备受关注。但随着辐射源频率的升高，器件尺寸逐渐减小，热阴极在其中的应用面临诸多限制。场致发射纳米冷阴极不受结构尺寸限制，应用于真空电子太赫兹辐射源中具有先天优势，但场致发射电子极易轰击阳极，电子注难于成形，导致纳米冷阴极应用受限。本项目首先对多种纳米冷阴极结构开展研究并获得相关优化设计及实验测试结果，最终成功实现电子零截获，电子注最大工作电流达到700mA。对利用微波毫米波调制纳米冷阴极场致发射过程进行研究，并设计出低电压紧凑型辐射源器件方案，在工作电压2.9kV时可产生0.14THz瓦级输出功率。开展磁控纳米冷阴极高次谐波倍频辐射源实验研究，并成功获得0.42THz输出信号。相关研究成果解决了研制纳米冷阴极太赫兹辐射源多项关键技术，同时也为场致发射纳米冷阴极在相关空天领域应用奠定基础。