Electronic and Magnetic Properties of Half Metallic Heusler Alloy Co2mnsi: A First-Principles Study

Abstract

Heusler alloys have been of great interest because of their application in the field of modern technological word. Electronic and magnetic properties of Co, Mn, Si and the Heusler alloy Co₂MnSi have been studied using Density functional theory based Tight Binding Linear Muffin Tin Orbital with Atomic Sphere Approximation (TB-LMTO-ASA) approach. From the calculation lattice parameter of optimized structure of Co, Mn, Si and Co₂MnSi are found to be 2.52A0 , 3.49A0 , 5.50A0 , 5.53A0 respectively. Band structure calculations show that Co and Mn are metallic, Si as semi-conducting while the Heusler alloy Co₂MnSi as half-metallic in nature with band gap 0.29eV. The charge density plot indicates major bonds in Co₂MnSi are ionic in nature. Magnetic property has been studied using the density of states (DOS), indicating that Co and Co₂MnSi are magnetic with magnetic moment 2.85μ_B and 4.91μ_B respectively. The contribution of orbitals in band, DOS and magnetic moment are due to d-orbitals of Co and Mn and little from s and p-orbital of Si in Co₂MnSi.

The Himalayan Physics Vol. 6 & 7, April 2017 (31-36)