Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5467630 | Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms | 2017 | 7 Pages |
Abstract
We study through time-dependent density-functional theory (TDDFT) method the electronic stopping power of low-energy protons and helium ions moving through CdTe under the condition of channeling. The agreement between our calculated results and SRIM data roughly up to the stopping maximum for the proton along the ã1 0 0ã and ã1 1 1ã crystalline axes and for helium ions along ã1 0 0ã crystalline axis is satisfactory, which can be explained by the energy transfer mechanism that electron-hole excitation caused by ions in the solid. However, in the channel of ã1 1 1ã for helium ions, a transition between two velocities regimes is observed at about v = 0.4 a.u. This may be an indication of extra energy loss channel beyond the electron-hole excitation. To analyze it, we calculate the amount of electrons captured by the moving projectiles in real time. It is found that the soft transition between two velocities regimes can be attributed to the charge transfer and charge resonance between helium ion and host atoms of CdTe crystal, which are considered as additional energy loss channels.
Related Topics
Physical Sciences and Engineering
Materials Science
Surfaces, Coatings and Films
Authors
Chang-kai Li, Fei Mao, Yan-long Fu, Bin Liao, Xiao-ping Ouyang, Feng-Shou Zhang,