(1. 河南理工大學(xué) 材料科學(xué)與工程學(xué)院 環(huán)境友好型無機(jī)材料重點(diǎn)實(shí)驗(yàn)室培育基地，焦作 454000；
2. 河南理工大學(xué) 數(shù)學(xué)與信息科學(xué)學(xué)院，焦作 454000；
3. 河南理工大學(xué) 物理與電子信息學(xué)院，焦作 454000；
4. 河南理工大學(xué) 材料科學(xué)與工程學(xué)院，焦作 454000)
摘 要: 采用基于密度泛函理論的第一性原理平面波贗勢方法，研究本征LiNbO3晶體以及Fe、La摻雜LiNbO3的電子結(jié)構(gòu)及光學(xué)性質(zhì)。計算LiNbO3晶體在不同摻雜體系下的折射率、反射率、吸收函數(shù)、能量損失譜以及光電導(dǎo)率等光學(xué)性質(zhì)。結(jié)果表明：本征LiNbO3晶體沒有磁性，但可以通過Fe原子的誘導(dǎo)產(chǎn)生自旋極化。Fe摻雜LiNbO3體系產(chǎn)生的總磁矩為8.54 μB，其主要是由Fe的3d軌道自旋極化引起的，而Fe原子提供的磁矩為3.40 μB。摻雜原子可以有效調(diào)控LiNbO3晶體的電子結(jié)構(gòu)和光學(xué)性質(zhì)，為改善LiNbO3晶體的性能提供了可靠的理論依據(jù)。
關(guān)鍵字: 電子結(jié)構(gòu)；光學(xué)性質(zhì)；磁性；第一性原理；LiNbO3
（1. Cultivating Base for Key Laboratory of Environment-Friendly Inorganic Materials in Henan Province,
School of Materials Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China;
2. School of Mathematics and Informatics, Henan Polytechnic University, Jiaozuo 454000, China;
3. School of Physics and Electronic Information Engineering, Henan Polytechnic University, Jiaozuo 454000, China;
4. School of Materials Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China）
Abstract:The electronic structures and optical properties of pure and Fe, La doped lithium niobate crystals (Fe, La: LiNbO3) were studied by first-principles methods based on density functional theory (DFT). Moreover, the refractive index, the reflectivity, absorption function, energy loss function and the conductivity of optical properties in different doped LiNbO3 crystals were calculated by CASTEP. The calculated results show that intrinsic LiNbO3 has no magnetic properties. However, Fe doped LiNbO3 can induce spin-polarization. The total magnetism of Fe doped LiNbO3 is 8.54 μB, which is attributed to the spin-polarization of 3d orbital of Fe, and the magnetism of Fe atom is 3.40 μB. The electronic structures and optical properties of LiNbO3 can be effectively modulated by the doped atoms, which provides a reliable support in theory for further applications of lithium niobate crystal with different doped atoms.
Key words: electronic structures; optical properties; magnetism; first-principles; LiNbO3
