Potential of LiMnX (X = Sn, In, Ge) Semheusler Alloys for Spintronic and Magnetic Sensor Applications

Abstract This study aims to theoretically investigate the potential of LiMnX (X = Sn, In, Ge) semi-Heusler alloys for use in magnetic sensor systems. These alloys, which have not been sufficiently studied theoretically or experimentally in the literature, were analyzed in terms of their structural, electronic, elastic, thermal, and vibrational properties within the framework of density functional theory (DFT). After confirming that the results obtained in this study are in good agreement with those reported by Damewood for the LiMnSi alloy, investigations were extended to other alloys. The results reveal that the LiMnGe alloy exhibits metallic behavior in the spin-up channel and semimetallic-like behavior in the spin-down channel with a 0.93 eV bandgap. LiMnSn and LiMnIn alloys exhibit metallic properties in both spin channels. Elastic modulus analyses indicate that all the alloys are mechanically stable, and this stability is supported by parameters such as the bulk modulus and Young's modulus. The high magnetic moment values of all the alloys (LiMnSn: 3.97 µ_B, LiMnIn: 3.72 µ_B, LiMnGe: 3.64 µ_B) provide an attractive foundation for magnetic sensor technologies. The Debye temperatures were calculated as 248 K for LiMnSn, 204 K for LiMnGe, and 97 K for LiMnIn. These values also support the thermal stability ranking of the alloys. As a result of these comprehensive analyses, preliminary information has been identified that could provide benefits for applications in magnetic sensor technologies using LiMnX alloys.