Physics Colloquium: Electronic, magnetic, and structural properties of CoVMnSb: ab initio study.

Wednesday, September 13, 2023 - 4:00 pm

Dr. Pavel Lukashev, Associate Professor of Physics at the University of Northern Iowa will be presenting his findings on electronic, magnetic, and structural properties of CoVMnSb: ab initio study. The generation of highly spin-polarized current is one of the key aspects investigated for potentialdevice applications in spin-based electronics (spintronics). In principle, the ideal material for such applications is a room temperature half-metal, i.e. a material that is conducting electrons of one spin only. He will present computational results on electronic, magnetic, and structural properties of CoVMnSb, a quaternary Heusler alloy. He will show that this material may crystallize in two energetically closestructural phases: inverted and regular cubic. The inverted cubic phase is the ground state, with ferrimagnetic alignment, and around 80% spin polarization. At the same time, the regular cubic phase isferromagnetic half-metal. The difference in the magnetic states of these two phases is explained by thedifference in calculated exchange coupling parameters between vanadium atom and its neighbors. Transition to regular cubic phase may be attained by applying uniform pressure. In practice, this pressuremay be realized by atomic substitution of non-magnetic atom (Sb) with another non-magnetic atom (Si)of smaller radius. More specifically, 25% substitution of Sb with Si results in half-metallic transition. Inaddition, CoVMnSb 0.5 Si 0.5 retains its half-metallic properties under a considerable range of mechanicalpressure, as well as exhibits thermodynamic stability, thus making this alloy attractive for potentialspintronic applications.

Begeman Hall Room 114
Contact Information
Paul Shand
(319) 273-2420