Electron- and Hole-Doped Hexagonal TbInO₃ from First Principles

In materials hosting frustrated magnetism, localized spins are acted upon by competing exchange interactions that cannot be satisfied at the same time, leading to a highly degenerate ground state. This can give rise to a fluid-like state of matter with no magnetic ordering known as a <i>spin liquid</i>. Spin liquids have been proposed to host exotic properties such as fractionalized charges and superconductivity upon doping, which are both of fundamental interest and may be of potential interest for quantum computing applications. However, the experimental confirmation of spin liquid states remains challenging, and there is a strong need for the identification of more candidate materials that may host spin liquids. Recent research has shown that hexagonal TbInO₃, with anisotropic exchange interactions, significant spin-orbit coupling, and f-electron magnetism, may be a spin-liquid candidate. TbInO₃has a hexagonal crystal structure consisting of layers of corner-sharing non-magnetic InO₅ trigonal bipyramids, separated by layers of Tb³⁺ions in a distorted triangular lattice with two inequivalent Tb sites. In this work, we use density functional theory (including spin-orbit coupling) to investigate the structural, electronic, and magnetic properties of hexagonal TbInO₃. We explore both undoped TbInO₃ as well as the effect of electron- or hole-doping by adding (removing) electrons from the calculation. By analyzing the density of states and band structure of doped TbInO₃, we explore whether added charge carriers are localized or form a metallic conducting state. Our work advances our fundamental understanding of charge-doping spin-liquid candidate TbInO₃.