arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1909.06245cond-mat.mtrl-sci
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keV能轻离子对过渡金属氮化物的电子激发

Electronic excitation of transition metal nitrides by light ions with keV energies

Barbara Bruckner, Marcus Hans, Tomas Nyberg, Grzegorz Greczynski, Peter Bauer, Daniel Primetzhofer

摘要:

我们研究了特定的电子能量沉积的质子和He离子与keV的能量在不同的过渡金属氮化物的技术利益。从两个不同的飞行时间离子散射装置获得的数据,并显示出良好的协议。对于质子与轻氮化物,即TiN,VN和CrN相互作用,发现每个原子非常相似的停止截面,这与文献数据的N2气体的初级能量<= 25 keV。在具有来自第5和第6周期的金属成分的化学上相当类似的氮化物(即ZrN和HfN)的情况下,测量的电子停止截面超过对于分子N2气体所观察到的。对于He离子,发现在所有氮化物中的电子能量损失显著高于N2气体的等效数据。此外,观察到的特定的电子能量损失的速度比例的偏差。与质子和He离子的密度泛函理论的预测比较,后者的射弹产生高的表观效率的电子激发的目标。这些发现被认为是指示的贡献,除了电子空穴对激发,如电子捕获和损失过程的弹丸或促进靶电子在原子碰撞的其他机制。

英文摘要:

We investigated the specific electronic energy deposition by protons and He ions with keV energies in different transition metal nitrides of technological interest. Data were obtained from two different time-of-flight ion scattering setups and show excellent agreement. For protons interacting with light nitrides, i.e. TiN, VN and CrN, very similar stopping cross sections per atom were found, which coincide with literature data of N2 gas for primary energies <= 25 keV. In case of the chemically rather similar nitrides with metal constituents from the 5th and 6th period, i.e. ZrN and HfN, the electronic stopping cross sections were measured to exceed what has been observed for molecular N2 gas. For He ions, electronic energy loss in all nitrides was found to be significantly higher compared to the equivalent data of N2 gas. Additionally, deviations from velocity proportionality of the observed specific electronic energy loss are observed. A comparison with predictions from density functional theory for protons and He ions yields a high apparent efficiency of electronic excitations of the target for the latter projectile. These findings are considered to indicate the contributions of additional mechanisms besides electron hole pair excitations, such as electron capture and loss processes of the projectile or promotion of target electrons in atomic collisions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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