Investigating the Structural, Electronic, Magnetic, Mechanical, Anisotropic and Optical Aspects of CoFeYSb (Y = V and Ti) Quaternary Heusler Alloys from First Principles

Abstract

This study employs first-principles calculations to explore the structural, elastic, electronic, magnetic, and optical properties of the quaternary Heusler compounds CoFeYSb (Y = V, Ti). The structural analysis confirms that both compounds are most stable in the YI configuration. CoFeVSb is found to exhibit ferromagnetic behavior, while CoFeTiSb shows ferrimagnetism. Elastic constants, cohesion energy, and formation energy calculations further validate the stability of the magnetic (I) phase for both materials. Band structure analysis reveals that these compounds are half-metallic, achieving 100% spin polarization at the Fermi level, with spin-down energy gaps of 0.55 eV for CoFeVSb and 0.61 eV for CoFeTiSb. The total magnetic moments comply with the Slater-Pauling 24-electron rule, with values of 3 μB for CoFeVSb and 2 μB for CoFeTiSb. Optical investigations, including the dielectric function, absorption coefficient, and energy loss function, demonstrate strong absorption in the visible and ultraviolet ranges. These results highlight the potential of CoFeYSb compounds for advanced optoelectronic and spintronic applications, offering new opportunities for their integration into electronic and photonic technologies.