Study of the Influence of Electron Spin in Ferromagnetism and Thermoelectric Characteristics of CdTm2Y4 (Y = S, Se) Spinels for Spintronic Applications

The current study used full-potential methods to examine the ferromagnetic characteristics of CdTm2Y4(Y= S, Se) spinels; i.e., structural, elastic, electronic, and thermoelectric characteristics of these spinels have been explored for the first time. We used PBEsol-GGA for enthalpy of formation calculations to explain the stability of the ferromagnetic state and calculate the elastic constants and corresponding mechanical modules to reveal the ductile behavior of the materials. The mBJ potential is used instead of PBEsol-GGA to obtain more accurate and precise results of electronic and thermoelectric characteristics. Using mBJ potential leads to complete occupation of the bands in the materials and a clear interpretation of the density of states (DOS). The analysis of the electronic band structure and DOS reveals the stability of the ferromagnetic state in the analyzed materials as a result of p-d hybridization-based exchange splitting of Tm cations in the lattice. The calculations of thermoelectric efficiency are effective in evaluating the aptitude pertinence of the material in waste energy recovery systems and other technological applications. The thermal parameters of these materials are also analyzed to examine their thermal stability over a wide range of temperatures. The results of these calculations are essential for determining the suitability of the materials for use in spintronics-based devices and thermoelectric appliances as these devices rely heavily on the material's thermoelectric properties.