Effect Of Doping On The Electronic Structure And Magnetic Properties Of Mn₃Ge And Ti₂Vsb

In recent years,with the rapid development of science and technology,new functional materials have been extensively studied.Half-metals are widely used in the field of spintronic devices because of their unique electronic structure?100%spin polarization?.The effect of C doping on the electronic structure and magnetic properties of Mn₃Ge has been studied by first-principles calculations.The effect of anti-site disorder on the electronic structure and magnetic properties of Ti₂VSb has also been studied.The related research of Mn₃Ge is summarized as follows:1.It is found that the energy is the lowest when the C atom is in the center of the octahedron.In other words,when the C atom is at?0.5,0.5,0.25?,the doped structure is the most stable.2.We find that the total magnetic moment of Mn₃GeC_x firstly decreases and then gradually increases with the carbon concentration increasing.The magnetic compensation is realized in Mn₃GeC_0.4.3.We also find that the total magnetic moment of the multilayers formed by the bulk structure of Mn₃GeC_0.4.4 is not zero.The related research of Ti₂VSb is summarized as follows:1.The effect of anti-site disorder on the electronic structure of Ti₂VSb was studied.And Ti₂VSb becomes a nearly fully compensated ferrimagnetic spin-gapless semiconductor when 25%content of Ti?A?atoms exchange their place with V atoms.2.The influence of tetragonal distortion on the electronic structure of Ti₂VSb is studied.It is found that the electronic structure of Ti₂VSb is sensitive to the tetragonal distortion and FCFS property can be maintained only when the c/a ratio is in the range of 0.95¹.04.When the c/a ratio is not in this range,Ti₂VSb is firstly transformed into a fully compensated ferrimagnetic half-metal and then gradually transformed into a normal ferrimagnetic metal.