Study of Curie Temperature, Ferromagnetism, and thermoelectric properties BaCo2Z4 (Z = S, Se, Te) for spintronic and energy applications

Spintronics is an emerging technology that harnesses electron spin to speed up data transfer, manipulation, and storage. In our thorough examination of BaCo₂Z₄ (Z = S, Se, Te), we have probed into electronic behaviour, Curie temperature, ferromagnetism, and thermoelectric behaviour. Our optimization analysis underscored the superior energy release of ferromagnetic states over antiferromagnetic counterparts, a finding substantiated by formation energy. We calculated spin polarization and Curie temperature using the Heisenberg model, confirming that ferromagnetism is prevalent at temperatures higher than room temperature. Including hybridization, crystal field energy, states density, band structures, exchange constants and energies, and the double exchange model, the investigation examined the complex nature of ferromagnetism. Importantly, shifting the magnetic moment away from Co and toward Ba and S/Se/Te sites revealed that electron spin, not clustering of Co’s magnetic ions, is the fundamental property of ferromagnetism. We also investigated thermoelectric metrics such as the Seebeck coefficient, conductivities, and power factor for spin (↑) and spin (↓), which helped us to understand the complex role of electron spin at high temperatures and their role in energy harvesting applications.