关键词: 半Heusler合金/
高自旋极化/
单原子链/
第一性原理计算
English Abstract
Single spin channels in Ni-doped CoTiSb semiconductor
Chang Yue-Hua1,Pan Ru-Jing1,
Si Yu-Hao1,
Lin Ting-Ting2,
Wu Zhi-Min1,
Liu Guo-Dong1,2,
Cui Yu-Ting1
1.School of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 400044, China;
2.School of Material Sciences and Engineering, Hebei University Technology, Tianjin 300130, China
Fund Project:Project supported by the National Natural Science Foundation of China (Grant No. 51271071), the Basic and Frontier Research Project of Chongqing City, China (Grant No. cstc2013jjB50001), the Chongqing City Funds for Distinguished Young Scientists, China (Grant No. cstc2014jcyjjq50003), and the Program for Top Young Talents of Hebei Province, China.Received Date:26 November 2015
Accepted Date:09 March 2016
Published Online:05 April 2016
Abstract:Since the spin-transfer effect was predicted in 1996, the direct-current-switched magnetic storage has received much attention. A slender nanopillar with high spin-polarized ratio of the conductive electrons is the most favorable for realizing the direct-current-switched magnetic memory. Wang et al. (Sup. Mic. 2015 86 493) showed a supercell idea used to design the nanopillar array in a semiconductor matrix. Based on this idea, in this paper, the Ni-based single atomic chains are designed in the semiconductive CoTiSb matrix by continuously substituting Ni for Ti, Sb, or Ti-Sb in the [001] crystallographic direction. These single atomic chains are uniformly distributed in the matrix. We investigate the electronic structures and magnetic properties of CoTiSb supercells with the Ni-based single atomic chains by using the first-principle calculations. The calculation results show that the single atomic chains of Ni-Sb (achieved by substituting Ni for Ti) have a high spin polarization and hole conduction properties. The single atomic chain of Ni-Ti (achieved by substituting Ni for Sb) and Ni-Ni single atomic chain (achieved by substituting Ni for Ti and Sb) both have a 100% spin polarization ration at the Fermi level. The Ni-based single atomic chain has an effect on the electronic structures of other atoms surrounding it in about a lattice length and forms a nanopillar with the center of the Ni-based single atomic chain. We predict that CoTiSb matrixes with the Ni-Ti and Ni-Ni single atomic chains will be good candidates for the direct-current-switched magnetic storage.
Keywords: half Heusler alloy/
high spin polarization/
single atomic chain/
first-principles calculations
