Gate-Tunable Magnetoresistance in Antiferromagnetic van der Waals FePS3 Transistors.

van der Waals (vdW) antiferromagnetic semiconductors combine electromagnetic control of device responses with the desirable advantages of antiferromagnets, including high switching speed and stability under stray magnetic fields. Of particular interest is FePS3 due to its unique combination of semiconducting behavior and highly anisotropic magnetic properties with metamagnetic transitions exceeding 30 T. Here, we demonstrate gate-tunable magnetotransport in FePS3 over a wide operating temperature range from 5 to 300 K by using vdW materials for all components in a field-effect transistor geometry. Magnetoresistance (MR) measurements reveal multiple crossings between negative and positive MR for these devices. Despite the strength of the antiferromagnetic order in FePS3, MR near the Néel temperature switches from negative to positive with increasing gate voltage, which is attributed to the stabilization of critical magnetic fluctuations. This demonstrated electrostatic tunability creates opportunities to employ antiferromagnets with large metamagnetic transition fields in spintronic applications.