Magnetic van der Waals (vdW) materials, including ferromagnets (FM) and antiferromagnets (AFM), have given access to the investigation of magnetism in two-dimensional (2D) limit and attracted broad interests recently. However, most of them are semiconducting or insulating and the vdW itinerant magnets, especially vdW itinerant AFM, are very rare. Here, we studied the anomalous Hall effect of a vdW itinerant magnet Fe5GeTe2 (F5GT) with various thicknesses down to 6.8 nm (two unit cells). Despite the robust ferromagnetic ground state in thin-layer F5GT, however, we show that the electron doping implemented by a protonic gate can eventually induce a magnetic phase transition from FM to AFM. Realization of an antiferromagnetic phase in F5GT highlights its promising applications in high-temperature antiferromagnetic vdW devices and heterostructures.
@article{arxiv.2012.00891,
title = {Gate-controlled magnetic phase transition in a van der Waals magnet Fe$_5$GeTe$_2$},
author = {Cheng Tan and Wen-Qiang Xie and Guolin Zheng and Nuriyah Aloufi and Sultan Albarakati and Meri Algarni and Jiangpeng Song and James Partridge and Dimitrie Culcer and Xiaolin Wang and Jiabao Yi and Yimin Xiong and Mingliang Tian and Yu-Jun Zhao and Lan Wang},
journal= {arXiv preprint arXiv:2012.00891},
year = {2021}
}