Identifying the fingerprints of topological states by tuning magnetoresistance in a semimetal: The case of topological half-Heusler Pt1−xAuxLuSb

Topological materials often exhibit remarkably linear, non-saturating magnetoresistance (LMR), which is both of scientific and technological importance. However, the role topologically non-trivial states in emergence such a behaviour has eluded clear demonstration experiments. Here, by reducing coupling between topological surface (TSS) bulk carriers we controllably tune LMR behavior Pt1-xAuxLuSb into distinct plateaus Hall resistance, show arise from quantum phase. This allowed us to reveal how smearing Landau levels, otherwise give rise phase, results an due strong interaction TSS with positive g-factor carriers. We establish that controlling strength can bring about dramatic changes their magnetotransport behavior. In addition, our work outlines strategy macroscopic physical observables compounds semi-metallic band structure, as case multi-functional Heusler compounds, thereby opening up opportunities for utilization hybrid structures.