title: Biaxial strain effect induced electronic structure alternation and trimeron recombination in Fe3O4.
abstract: The Verwey transition in Fe3O4is the first metal-insulator transition caused by charge ordering. However, the physical mechanism and influence factors of Verwey transition are still debated. Herewith, the strain effects on the electronic structure of low-temperature phase (LTP) Fe3O4with P2/c and Cc symmetries are investigated by first-principles calculations. LTP Fe3O4with each space group has a critical strain. With P2/c, Fe3O4is sensitive to the compressive strain, but it is sensitive to tensile strain for Cc. In the critical region, the band gap of LTP Fe3O4with both two symmetries linearly increases with strain. When strain exceeds the critical value, DOS of spin-down t2gelectron at Fe(B4) with P2/c and Fe(B42) with Cc changes between dx2-y2 and dxz+ dyz. The trimerons appear in Cc can be affected by strain. With a compressive strain, the correlation of trimeron along x and y axes is strengthened, but broken along the face diagonal of FeB4O4, which is opposite at the tensile strains. The results suggest that the electronic structure of Fe3O4is tunable by strain. The narrower or wider band gap implies a lower or higher transition temperature than its bulk without strains, which also gives a glimpse of the origin of charge-orbital ordering in Fe3O4.
authors.affiliation: Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, Faculty of Science, Tianjin University, Tianjin 300072, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Liu
authors.affiliation: Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, Faculty of Science, Tianjin University, Tianjin 300072, China.
authors.forename: Li
authors.initials: L
authors.lastname: Yin
authors.affiliation: Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, Faculty of Science, Tianjin University, Tianjin 300072, China.
authors.forename: Wenbo
authors.initials: W
authors.lastname: Mi