Recently, Professor Ren Junfeng and his team from The School of Physics and Electronic Science of Shandong Normal University published a paper entitled "Electrical Control of the Valley-Layer" in the internationally renowned Journal of Physical Chemistry Letters Hall Effect in Ferromagnetic Bilayer Lattices ". Shandong Normal University is the sole author of the paper. Master student Cheng Haomiao is the first author, and Professor Ren Junfeng and Dr. Zhao Xiuwen are the corresponding authors.

Layer electronics and valley electronics based on layer and valley degrees of freedom are of great significance to the manufacture and application of new generation electronic devices. Although the layer Hall effect has been realized theoretically and experimentally, it is primarily based on topology and antiferromagnetic lattices. Based on the low energy efficient k·p model, we study the mechanism of controllable valley Hall effect (V-LHE) in a double-layer ferromagnetic lattice, and propose that V-LHE can be generated by interlayer slip in a double-layer ferromagnetic lattice. V-LHE based on valley, layer degrees of freedom, ferromagnetic and ferroelectric coupling can be predicted due to the breaking of the time inversion and space inversion symmetries. In addition, valley and layer degrees of freedom can be controlled by magnetization direction and interlayer slip respectively. The authors also demonstrated this mechanism in a real system bilayer CrSI lattice by first principles calculations, and found that V-LHE can be effectively regulated by a vertical external electric field. These findings provide a new research platform for valley and layer electronics.

The above research was supported by the National Natural Science Foundation of China, the Natural Science Foundation of Shandong Province and the Youth Innovation Science and Technology Program of Shandong Province.

The thesis links: https://doi.org/10.1021/acs.jpclett.4c02090