Rare earth based MgPm2X4 (X = S, Se) spinel chalcogenides for spintronic and thermoelectric applications

Abstract

In current report, the structural, magnetic, and thermoelectric properties of RE doped MgPm2X4 (X = S, Se) spinels were investigated. The energy difference in ferromagnetic and antiferromagnetic states reveals the stability of MgPm2(S/Se)4 in the ferromagnetic states. The computation of enthalpy of formation also ascertains thermodynamic stability of crystal structure. Spin-dependent band structure and density of states analysis reveal ferromagnetic semiconducting character showing different electronic behavior in both spin channels. The room temperature ferromagnetism, spin polarization and Curie temperature are estimated from exchange energies analysis. In addition, exchange constants (N0α and N0β), exchange energy Δx(pd), crystal field energy, and double exchange mechanism were studied to explore the magnetic response. Likewise, the electrical conductivity, thermal conductivity, Seebeck co-efficient, and power factor show effect on electrons spin and their potential for thermoelectric devices.