Thermodynamic and electrical transport properties of the half-Heusler plumbide TbAuPb

Structural, thermodynamic and electrical transport properties of TbAuPb were investigated on single crystals. The compound was found to crystallize with the cubic MgAgAs-type structure characteristic of half-Heusler materials. It orders antiferromagnetically at TN = 5 K and undergoes a transition into a different antiferromagnetic phase emerging in high magnetic fields. Electrical transport in TbAuPb exhibits a multiband character, with a predominance of hole-like carriers. Angular magnetoresistance evolves systematically with applied magnetic field and changes its symmetry near the spin-reorientation transition, highlighting strong coupling between the charge transport and the magnetic order. The results of first-principles calculations indicate that TbAuPb is a band inverted semimetal in the non-magnetic state, which becomes topologically trivial in the field-induced ferromagnetic state.