High electron mobility and large magnetoresistance in the half-Heusler semimetal LuPtBi

Materials with high carrier mobility showing large magnetoresistance (MR) have recently received much attention because of potential applications in future high-performance magnetoelectric devices. Here, we report on an electron-hole-compensated half-Heusler semimetal LuPtBi that exhibits an extremely high electron mobility of up to 790.16em0ex0000.16em0excm²/V0.16em0exs with a nonsaturating positive MR as large as $3200%$ at 2 K. Remarkably, the mobility at 300 K is found to exceed 100.16em0ex5000.16em0excm²/V0.16em0exs, which is among the highest values reported in three-dimensional bulk materials thus far. The clean Shubnikov--de Haas quantum oscillation observed at low temperatures and the first-principles calculations together indicate that the high electron mobility is due to a rather small effective carrier mass caused by the distinctive band structure of the crystal. Our findings provide a different approach for finding large, high-mobility MR materials by designing an appropriate Fermi surface topology starting from simple electron-hole-compensated semimetals.