标题： 超纳米晶金刚石光电阴极的平均横向能量 显示英文标题

标题： Mean Transverse Energy of Ultrananocrystalline Diamond Photocathode

摘要： 掺氮超纳米晶体金刚石((N)UNCD)由于其高发射率，可能成为光阴极应用的启用材料平台。 尽管许多研究小组报道了UNCD的量子效率(QE)，但尚未有实验测量关于本征发射率/平均横向能量(MTE)的报告。 本文描述了在光子能量范围4.41至5.26 eV内的(N)UNCD光阴极的MTE测量结果。 MTE表现出对光子能量不明显的依赖性，平均值为266 meV。 这种光谱行为被证明与物理或化学表面粗糙度无关，并且与石墨晶界处的低电子有效质量发射不一致，但可能与金刚石晶粒之间的石墨区域中空间限制状态的发射有关。 快速生长的QE和相对于过量激光能量的恒定MTE的综合作用可能会为高亮度UNCD光阴极铺平道路。 显示英文摘要

摘要： Nitrogen incorporated ultrananocrystalline diamond ((N)UNCD) could be an enabling material platform for photocathode applications due to its high emissivity. While the quantum efficiency (QE) of UNCD was reported by many groups, no experimental measurements of the intrinsic emittance/mean transverse energy (MTE) have been reported. Here, MTE measurement results for an (N)UNCD photocathode in the photon energy range of 4.41 to 5.26 eV are described. The MTE demonstrates no noticeable dependence on the photon energy, with an average value of 266 meV. This spectral behavior is shown to not to be dependent upon physical or chemical surface roughness and inconsistent with low electron effective mass emission from graphitic grain boundaries, but may be associated with emission from spatially-confined states in the graphite regions between the diamond grains. The combined effect of fast-growing QE and constant MTE with respect to the excess laser energy may pave the way to bright UNCD photocathodes.