V,Cr,Mn掺杂MoS_2磁性的第一性原理研究

Magnetism of V, Cr and Mn doped MoS_2 by first-principal study

基于第一性原理的自旋极化密度泛函理论分别研究了过渡金属V,Cr,Mn掺杂单层MoS2的电子结构、磁性和稳定性.结果表明:V和Mn单掺杂均能产生一定的磁矩,而磁矩主要集中在掺杂的过渡金属原子上,Cr单掺杂时体系不显示磁性.进一步讨论双原子掺杂MoS2体系中掺杂原子之间的磁耦合作用发现,Mn掺杂的体系在室温下显示出稳定的铁磁性,而V掺杂则表现出非自旋极化基态.形成能的计算表明Mn掺杂的MoS2体系相对V和Cr掺杂结构更稳定.由于Mn掺杂的MoS2不仅在室温下可以获得比较好的铁磁性而且其稳定性很高,有望在自旋电子器件方面发挥重要的作用.

According to density functional theory of first-principles calculations theory, we systematically study the electronic structures, magnetisms and stabilities of transition metal （TM = V, Cr, Mn） doped MoS2 single-layers. The results show that V- and Mn- monodoped systems each have magnetism and the magnetic moment mainly concentrates on the transition metal dopant atom, but Cr-doped MoS2 does not display magnetism. Further study on the magnetic coupling of double atoms doped MoS2 shows that the stable ferromagnetic state at room temperature is observed in the Mn-doped MoS2. However, the system shows a non-spin,polarization state due to doping with V. The calculated formation energy indicates that the Mn-doped MoS2 is the most stable system. Therefore, Mn-doped single-layer MoS2 maybe have potential applications in the spin electronic devices due to its good ferromagnetism and reliable stability.