Hidden nontrivial Berry phase and spin-zero effect in Te nanowires

The pi phase shift of quantum oscillations is generally believed to be a smoking gun evidence for nontrivial Berry phase. However, the spin-zero effect, a sign reversal of quantum oscillations at different magnetic field directions, adds an additional pi phase shift. Thus, the nontrivial Berry curvature can be concealed by the spin -zero effect, resulting in an apparent trivial phase in quantum oscillation measurements. In this work, we report a hidden Berry phase in Weyl semiconductor Te nanowires. A trivial-like Berry phase is observed in the quantum oscillations in Te nanowires. However, a large g factor, together with the band evolution under magnetic fields, leads to a spin-zero effect in Te nanowires. We further derive the nontrivial nature of Te nanowires from quantum transport.