Zhao Xu, Huang Ranzhuo, Wang Tianxing, Dai Xianqi, Wei Shuyi, Ma Yaqiang
School of Physics, Henan Normal University, Xinxiang, Henan 453007, China.
Phys Chem Chem Phys. 2020 Mar 14;22(10):5765-5773. doi: 10.1039/c9cp06249a. Epub 2020 Feb 27.
Based on density functional theory, the electronic structure and magnetic properties of monolayer PtSe doped with different atoms were studied. The Pt and Se atoms are replaced by a transition metal atom (Mn) and a non-metal atom X (X = N, P, As), respectively. The pristine monolayer PtSe is a semiconductor with an indirect band gap of 1.352 eV. For one non-metal atom doping, the doped system exhibits indirect band gap magnetic semiconducting properties and the magnetic moment is less than 1 μ and mainly comes from the hybridization of Pt-5d and X-p orbitals. The N-Doped system still retains the magnetic semiconducting properties under strain (from -10% to 13%) and the band gap varies from 0.059 eV to 1.308 eV. For two X doped systems, three different configurations are considered. The doped systems retain the indirect band gap semiconducting properties except for the third nearest neighbor N-doped system (direct band gap). But, for all N-doped and the second nearest neighbor P-doped systems, the magnetic moment increases to more than double. Meanwhile, all X-doped monolayer PtSe systems exhibit p-type semiconducting characteristics. For (Mn, X) co-doped systems, the magnetic moments are mainly localized in the Mn 3d orbital and there is strong p-d hybridization between Mn atoms and X atoms. The (Mn, N/P) co-doped system still exhibits magnetic semiconducting properties. These results are important for designing semiconductor devices and electronic spin devices based on monolayer PtSe.
基于密度泛函理论，研究了不同原子掺杂的单层PtSe的电子结构和磁性。Pt原子和Se原子分别被过渡金属原子（Mn）和非金属原子X（X = N、P、As）取代。原始的单层PtSe是一种间接带隙为1.352 eV的半导体。对于单非金属原子掺杂，掺杂体系表现出间接带隙磁性半导体性质，磁矩小于1 μ，主要源于Pt-5d和X-p轨道的杂化。N掺杂体系在应变（-10%至13%）下仍保留磁性半导体性质，带隙在0.059 eV至1.308 eV之间变化。对于两个X掺杂体系，考虑了三种不同构型。除了第三近邻N掺杂体系（直接带隙）外，掺杂体系保留间接带隙半导体性质。但是，对于所有N掺杂和第二近邻P掺杂体系，磁矩增加到两倍以上。同时，所有X掺杂的单层PtSe体系都表现出p型半导体特性。对于（Mn，X）共掺杂体系，磁矩主要定域在Mn 3d轨道上，Mn原子和X原子之间存在强烈的p-d杂化。（Mn，N/P）共掺杂体系仍表现出磁性半导体性质。这些结果对于基于单层PtSe设计半导体器件和电子自旋器件具有重要意义。
