Probing giant Zeeman shift in vanadium-doped WSe2 via resonant magnetotunneling transport

Abstract

© 2021 American Physical Society.Doping van der Waals layered semiconductors with magnetic atoms is a simple and effective approach to induce magnetism. However, investigation of the electrical properties of such two-dimensional semiconductors and the modulation of their magnetic order for spintronics is still lacking. Herein, we report a giant Zeeman shift from the spin-polarized state in tungsten diselenide (WSe2) doped with a small amount of vanadium (V) atoms (∼0.1%). The Zeeman shift was measured via resonant magnetotunneling spectroscopy with a vertical graphite/V-WSe2/graphite heterojunction. The p-type doping state near the valence band is substantially shifted under an external magnetic field by 7.8 meV/T, equivalent to a giant g factor of approximately 135, an order of magnitude higher than that of other two-dimensional magnetic semiconductors. The ferromagnetic order of the spin glass state and its long-range interaction are revealed by the remanence of magnetoresistance between the zero-field cooling and field-cooling processes as well as magnetoresistance hysteresis. The ferromagnetic glass order is fully established at 50 K, whereas the long-range interaction persists at higher temperatures of up to 300 K in V-doped WSe2 flakes with an approximate thickness of 5 nm. Our work sheds light on the magnetic nature of V-doped WSe2 semiconductors and paves the way for future spintronics based on two-dimensional van der Waals magnetic semiconductors.