【摘要】 为满足太赫兹行波管对大电流密度、小型化阴极的需求，对自支撑碳纳米管(Carbon Nanotubes, CNTs)薄膜、自支撑石墨烯薄膜(Graphene Film, GF)以及CNTs绞线进行结构设计，并对其场发射性能进行了测试。结果表明，5mm边缘长度的自支撑CNTs薄膜在电流达到21mA时可保持稳定发射，最大发射电流可达26.5mA,发射电流密度为8.83 A/cm~2;10mm边缘长度的自支撑GF最大发射电流为25mA,发射电流密度为17.9A/cm~2,是自支撑CNTs薄膜的两倍；直径为60mm的CNTs绞线最大发射电流为7.6mA,发射电流密度可高达268.9 A/cm~2。这些阴极可以产生足以驱动器件工作的电流，能够为带状注、圆形注太赫兹行波管选择阴极提供参考。更多还原

【Abstract】 In order to meet the requirements of terahertz traveling wave tubes for high current density and miniaturized cathodes, free-standing carbon nanotube films, free-standing graphene films, and carbon nanotube yarns with different structures are designed and prepared, and the emission performances of them are tested. The free-standing carbon nanotube film with a 5 mm edge can maintain stable emission current of 21 mA. It can get a maximum current of 26.5 mA with an emission current density of 8.83 A/cm~2. The maximum emission current of the free-standing graphene film with a 10 mm edge is 25 mA, and the emission current density is 17.9 A/cm~2, which is twice that of the free-standing carbon nanotube film. The maximum emission current of the carbon nanotube yarn with a diameter of 60 μm is 7.6 mA,and the emission current density is as high as 268.9 A/cm~2. These cathodes can generate sufficient current to drive the device operation, providing a reference for cathode selection for sheet beam and circular beam terahertz traveling wave tubes.更多还原