The recently discovered antiferromagnetic topological insulator MnBi2Te4 hosts a variety of exotic topological quantum phases such as the axion insulator and Chern insulator states. Here we report systematic gate voltage dependent magneto transport studies in six septuple-layer MnBi2Te4. In p-type carrier regime, we observe positive linear magnetoresistance when MnBi2Te4 is polarized in the ferromagnetic state by an out-of-plane magnetic field. Whereas in n-type regime, distinct negative magnetoresistance behaviors are observed. The magnetoresistance in both regimes is highly robust against temperature even up to the N\'eel temperature. Within the antiferromagnetic state, the behavior of magnetoresistance exhibits a transition from negative to positive as applying a gate voltage. The boundaries between different magnetoresistance behaviors in the experimental phase diagram can be explicitly characterized by the gate-voltage-independent magnetic fields that denotes the processes of the spin-flop transition. The rich transport phenomena demonstrate the intricate interplay between topology, magnetism and dimensionality in MnBi2Te4.
@article{arxiv.2110.03164,
title = {Gate-tunable magnetoresistance in six-septuple-layer MnBi$_2$Te$_4$},
author = {Yaoxin Li and Chang Liu and Yongchao Wang and Hao Li and Yang Wu and Jinsong Zhang and Yayu Wang},
journal= {arXiv preprint arXiv:2110.03164},
year = {2021}
}