Pressure-Modulated Structural and Magnetic Phase Transitions in Two-Dimensional FeTe: Tetragonal and Hexagonal Polymorphs

Wuxiao Han; Jiajia Feng; Hongliang Dong; Mo Cheng; Liu Yang; Yunfei Yu; Guoshuai Du; Jiayin Li; Yubing Du; Tiansong Zhang; Zhiwei Wang; Bin Chen; Jianping Shi; Yabin Chen

arXiv · 2311.18282

Pressure-Modulated Structural and Magnetic Phase Transitions in Two-Dimensional FeTe: Tetragonal and Hexagonal Polymorphs

Wuxiao Han·Jiajia Feng·Hongliang Dong·Mo Cheng·Liu Yang·Yunfei Yu·Guoshuai Du·Jiayin Li·Yubing Du·Tiansong Zhang·Zhiwei Wang·Bin Chen·Jianping Shi·Yabin Chen

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Abstract

Two-dimensional (2D) Fe-chalcogenides with rich structures, magnetisms and superconductivities are highly desirable to reveal the torturous transition mechanism and explore their potential applications in spintronics and nanoelectronics. Hydrostatic pressure can effectively stimulate novel phase transitions between various ordered states and to plot the seductive phase diagram. Herein, the structural evolution and transport characteristics of 2D FeTe were systematically investigated under extreme conditions through comparing two distinct symmetries, i.e., tetragonal (t-) and hexagonal (h-) FeTe. We found that 2D t-FeTe presented the pressure-induced transition from antiferromagnetic to ferromagnetic states at ~ 3 GPa, corresponding to the tetragonal collapse of layered structure. Contrarily, ferromagnetic order of 2D h-FeTe was retained up to 15 GPa, evidently confirmed by electrical transport and Raman measurements. Furthermore, the detailed P-T phase diagrams of both 2D t-FeTe and h-FeTe were mapped out with the delicate critical conditions. We believe our results can provide a unique platform to elaborate the extraordinary physical properties of Fe-chalcogenides and further to develop their practical applications.

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Wuxiao Han, Jiajia Feng, Hongliang Dong, Mo Cheng, Liu Yang, Yunfei Yu, Guoshuai Du, Jiayin Li, Yubing Du, Tiansong Zhang, Zhiwei Wang, Bin Chen, Jianping Shi, Yabin Chen. 2023-11-30. Pressure-Modulated Structural and Magnetic Phase Transitions in Two-Dimensional FeTe: Tetragonal and Hexagonal Polymorphs. https://arxiv.org/abs/2311.18282

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