Electronic stopping of slow protons in ZnO, VO2 (metal and semiconductor phases), HfO2, and Ta2O5 was investigated experimentally. As a comparison of the resulting stopping cross sections (SCS) to data for Al2O3 and SiO2 reveals, electronic stopping of slow protons does not correlate with electronic properties of the specific material such as band gap energies. Instead, the oxygen 2p states are decisive, as corroborated by density functional theory calculations of the electronic densities of states. Hence, at low ion velocities the SCS of an oxide primarily scales with its oxygen density.
@article{arxiv.1710.07994,
title = {Electronic Stopping of Slow Protons in Oxides: Scaling Properties},
author = {D. Roth and B. Bruckner and G. Undeutsch and V. Paneta and A. I. Mardare and C. L. McGahan and M. Dosmailov and J. I. Juaristi and M. Alducin and J. D. Pedarnig and R. F. Haglund, and D. Primetzhofer and P. Bauer},
journal= {arXiv preprint arXiv:1710.07994},
year = {2017}
}