First Principles Study of Electronic, Magnetic and Thermoelectric Properties of Perovskite BaTbO₃

Perovskite material have been on focus for many applications in spintronic device due to their novel properties such as ferroelectric, metal-insulator-transition, half-metallicity, non-trivial topological properties, etc. Recently these materials are found to show interesting thermoelectric properties which are expected to lead to new devices to harvest waste heat into efficient energy. In this work, we have investigated the electronic, magnetic, and thermoelectric properties of BaTbO₃ using the density functional formalism. The structure are fully relaxed and the value of the calculated lattice constant is 4.29 Å, in good agreement with the experimental values. The magnetic ground state of BaTbO₃ is found to be G-type antiferromagnet, with a band gap of 1.68 eV with an on-site Coulomb interaction of 4 eV for Tb atoms. Transport properties is computed using the BoltzTrap code. The calculated figure of merit (ZT) is 0.97 at 800 K, which indicates the suitability of BaTbO₃ as an efficient thermoelectric material.