中国物理B ›› 2016, Vol. 25 ›› Issue (7): 76601-076601.doi: 10.1088/1674-1056/25/7/076601
• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇 下一篇
Molecular dynamics simulation of nanoscale surface diffusion of heterogeneous adatoms clusters
Muhammad Imran, Fayyaz Hussain, Muhammad Rashid, Muhammad Ismail, Hafeez Ullah, Yongqing Cai, M Arshad Javid, Ejaz Ahmad, S A Ahmad
- 1 Material Simulation Research Laboratory (MSRL), Department of Physics, Bahauddin Zakariya University, Multan 60800, Pakistan;
2 Department of Physics, COMSATS Institute of Information Technology, 44000 Islamabad, Pakistan;
3 Department of Physics, Govt. College University Faisalabad, Layyah Campus, Layyah 31200, Pakistan;
4 Institute of High Performance Computing, A*STAR, Singapore 138632, Singapore;
5 Department of Basic Sciences (Physics), UET, Taxila;
6 Department of Physics, Simulation Laboratory, the Islamia University of Bahawalpur, 63100, Pakistan
Molecular dynamics simulation of nanoscale surface diffusion of heterogeneous adatoms clusters
Muhammad Imran1, Fayyaz Hussain1, Muhammad Rashid2, Muhammad Ismail3, Hafeez Ullah1,6, Yongqing Cai4, M Arshad Javid5, Ejaz Ahmad1, S A Ahmad6
- 1 Material Simulation Research Laboratory (MSRL), Department of Physics, Bahauddin Zakariya University, Multan 60800, Pakistan;
2 Department of Physics, COMSATS Institute of Information Technology, 44000 Islamabad, Pakistan;
3 Department of Physics, Govt. College University Faisalabad, Layyah Campus, Layyah 31200, Pakistan;
4 Institute of High Performance Computing, A*STAR, Singapore 138632, Singapore;
5 Department of Basic Sciences (Physics), UET, Taxila;
6 Department of Physics, Simulation Laboratory, the Islamia University of Bahawalpur, 63100, Pakistan
摘要： Molecular dynamics simulation employing the embedded atom method potential is utilized to investigate nanoscale surface diffusion mechanisms of binary heterogeneous adatoms clusters at 300 K, 500 K, and 700 K. Surface diffusion of heterogeneous adatoms clusters can be vital for the binary island growth on the surface and can be useful for the formation of alloy-based thin film surface through atomic exchange process. The results of the diffusion process show that at 300 K, the diffusion of small adatoms clusters shows hopping, sliding, and shear motion; whereas for large adatoms clusters (hexamer and above), the diffusion is negligible. At 500 K, small adatoms clusters, i.e., dimer, show almost all possible diffusion mechanisms including the atomic exchange process; however no such exchange is observed for adatoms clusters greater than dimer. At 700 K, the exchange mechanism dominates for all types of clusters, where Zr adatoms show maximum tendency and Ag adatoms show minimum or no tendency toward the exchange process. Separation and recombination of one or more adatoms are also observed at 500 K and 700 K. The Ag adatoms also occupy pop-up positions over the adatoms clusters for short intervals. At 700 K, the vacancies are also generated in the vicinity of the adatoms cluster, vacancy formation, filling, and shifting can be observed from the results.
中图分类号: (Mass diffusion, including self-diffusion, mutual diffusion, tracer diffusion, etc.)
- 66.10.cg