Phonon-scattering-induced linear magnetoresistance in the quantum limit up to room temperature.

Quantum transport at elevated temperatures is essential for unveiling novel physics and developing quantum devices. Here, we report quantum linear magnetoresistance in the Weyl semiconductor tellurium at temperatures from 40 to 300 K under magnetic fields up to 60 T. The inverse temperature dependence of the linear slopes for both transverse and longitudinal magnetoresistance provides clear evidence that the linear magnetoresistance originates from phonon scattering in the quantum limit. The unique Weyl band features large Landau level gaps that suppress thermal excitation, preserving Landau quantization and confining majority carriers to the lowest Landau level even at room temperature, ultimately enabling quantum linear magnetoresistance. This phonon-mediated mechanism is fundamentally distinct from previous findings, offering an innovative route to high-temperature quantum transport. Our work highlights the pivotal role of electron-phonon interaction in the quantum-limit regime and establishes strong magnetic fields at high temperatures as a promising platform for exploring novel quantum phenomena.