Lattice Dynamics, Mechanical Properties, Electronic Structure and Magnetic Properties of Equiatomic Quaternary Heusler Alloys CrTiCoZ (Z =Al,Si) using first principles calculations

Abstract: First principles calculations are performed to investigate the thermodynamical stability, dynamical, mechanical, electronic and magnetic properties of CrTiCoZ (Z= Al/Si) novel quaternary Heusler alloys. Y-type III atomic configuration is found to be the most stable structure for both compounds. The melting temperatures of both compounds are as high as 2142 K and 2420 K for CrTiCoAl and CrTiCoSi, respectively. The electronic structure calculations using GGA-PBE approach show a half metallic behavior of CrTiCoAl. The spin-down channel exhibits a direct band gap of 0.15 eV, whereas the spin-up channel is metallic making CrTiCoAl a half metallic ferromagnet with 100% spin polarization and an appreciable magnetic moment of -2 Bohr Magnetons. The Curie temperature of CrTiCoAl is well above the room temperature (385K), whereas that of CrTiCoSi is below the room temperature (203K).