兴奋剂
安培
材料科学
化学
物理
光电子学
热力学
电流(流体)
作者
Shuyu LÜ,Jianwei LI,Hao Jin,Yadong Wei,Jian Wang
出处
期刊:Journal of Shenzhen University Science and Engineering
[Science Press]
日期:2022-09-01
卷期号:39 (5): 489-496
标识
DOI:10.3724/sp.j.1249.2022.05489
摘要
LaMnO3 is an insulator with perovskite structure, which attracts the intense attention due to its promising properties. However, the previous studies mainly focused on the p-type doping of LaMnO3, while the n-type doping is under investigated. The effects of doping with various concentrations on the lattice structure, energy band and optical absorption of La1-x Hf x MnO3, as well as the spin valve device consisted of La1-x Hf x MnO3 scattering region sandwiched by two Ba doped LaMnO3 probes, are studied by the first-principles calculations based on the density functional theory. The results show that the antiferromagnetic or ferrimagnetic structure rather than the ferromagnetic structure is the ground state for La1-x Hf x MnO3. Hf elements exist in La1-x Hf x MnO3 as stable Hf 4+ ions, showing the properties of n-type doping. When the HF doping concentration x is small (i.e. x ≤ 0.031), the bandgap of La1-x Hf x MnO3 is close to that of the undoped intrinsic phase LaMnO3, and an isolated impurity level due to Hf doping is formed in the bandgap. The optical absorption spectrum of La1-x Hf x MnO3 shows that its optical absorption edge appears a red shift and the optical bandgap decreases with the increase of x. Meanwhile, the spin valve device composed of La3/4Ba1/4MnO3 as the left and right electrodes and La3/4Hf1/4MnO3 as the center layers is calculated, and the magnetoresistance near the Fermi level reaches about ~ (2.8 × 105)%. Through the gate voltage manipulation, the magnetoresistance can reach up to ~ (5.1 × 105)%. Our work provides a theoretical guideline for design of novel spintronic devices.
科研通智能强力驱动
Strongly Powered by AbleSci AI