Study links unusual ZrTe5 oscillations to reentrant Landau levels

Researchers studying zirconium pentatelluride reported quantum oscillations that persisted beyond the quantum limit under magnetic fields up to 60 tesla and temperatures near 0.7 kelvin. Their experiments and calculations attribute the effect to reentrant Landau levels: strong spin-orbit coupling causes levels to bend back toward and cross the Fermi level again. The team said a single-particle three-dimensional Dirac model reproduced the observed regimes without requiring many-body interactions. The result was obtained in a low-carrier-density sample using specialized high-field facilities.