Fe原子吸附的锑烯/WS_(2)异质结的磁电子性质及调控效应

Magneto-electronic properties and manipulation effects of Fe-adsorbed Sb/WS_(2)heterostructure

为研究非磁性二维范德瓦耳斯异质结吸附磁性原子的诱发磁性机理及磁电子特性,构键了锑烯(Sb)/WS_(2)异质结,并考虑Fe原子的多种吸附.计算的吸附能表明:T_(W),T_(S_m)及V_(Sb)吸附方式是Fe原子分别吸附于异质结下方、层间以及上方的最可能吸附位置,产生的磁性与Fe原子被吸附后其电子构型(VEC)扩展以及电荷转移使得电子自旋重排有关.TW,T_(S_m)吸附使无磁半导体性的异质结成为半-半导体(HSC),而V_(Sb)吸附对应双极化磁性半导体(BMS).特别是,计算的磁化能表明:层间T_(S_m)吸附使异质结具有最高的磁稳定性,足以抵抗常温热起伏对磁性的影响.量子调控能使异质结产生丰富的磁性,特别是磁相的灵活改变,如施加外加电场可使异质结实现HSC,HM(半金属)及BMS等磁相转换,而垂直应变则可使异质结发生HSC,HM及MM(磁金属)等磁相的转换.这一研究表明利用异质结能增加过渡金属原子的吸附区域(下方、层间以及上方),从而产生丰富的磁性,特别是层间吸附过渡金属,其磁性的温度稳定性能显著提高.

To study the induced magnetism mechanism and magneto-electronic properties of non-magnetic two- dimensional van der Waals heterostructure adsorbing magnetic atoms, we construct Sb/WS_(2) heterostructure, and consider its adsorbed Fe atoms. The calculated adsorption energy shows that T_(W), V_(Sb )adsorption are the most likely positions for Fe atom adsorbed below and above the heterostructure, respectively, and T_(S_M) adsorption is the most likely position for Fe atom adsorbed between two monolayers. The induced magnetism is due to the electron-spin rearrangement caused by the expansion of valence electronic configuration (VEC) and charge transfer after Fe atoms have been adsorbed. The TW adsorption and the T_(S_M) adsorption make the nonmagnetic semiconducting heterostructure become a half-semiconductor (HSC), while V_(Sb) adsorption turns the heterostructure into a bipolar magnetic semiconductor (BMS). In particular, the calculated magnetized energy indicates that the interlayer T_(S_M) adsorption leads the heterostructure to holding the highest magnetic stability, which is enough to resist the influence of thermal fluctuation at room temperature. Quantum manipulation can cause the heterostructure to produce abundant magnetism, especially the flexible change of magnetic phase. For example, the application of external electric field can give rise to the magnetic phase transition among HSC, HM (half-metal) and BMS for the heterostructure, and the vertical strain can make the heterostructure realize the magnetic phase transition among HSC, HM and MM (magnetic metal). This study shows that the heterostructure can increase the adsorption region of transition metal atoms (below, interlayer and above), so as to produce rich magnetism, especially for the interlayer adsorption of transition metals, its magnetic stability against temperature is significantly enhanced.