Realizing Ferromagnetism in a Field‐Effect Transistor Based on VSe2 Thin Flakes

Abstract

AbstractFerromagnetic order in 2D2D materials has triggered widespread interest because of their applications in spintronic devices. Monolayer 1T‐VSe2, as a recently emerged candidate of 2D2D ferromagnetic material, exhibits complicated behaviors that contradict the theoretical predictions. In this work, a systematic investigation is presented on the evolution of the transport properties in VSe2 thin flakes controlled by gate voltage. Notably, for the first time, a paramagnetic‐to‐ferromagnetic transition is realized in a VSe2 thin flake using a field‐effect transistor setup with solid ion conductor of polycrystalline Li1+x+yAlx(Ti2−yGey)P3−zSizO12 serving as the gate dielectric. The Curie temperature determined from the electrical transport measurements is ≈40 K. The electric‐field‐controlled ferromagnetism in exfoliated VSe2 flakes provides an excellent platform for developing advanced spintronics as well as investigating unusual emergent physics in 2D systems.