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arXiv · 2201.07635

Pressure-Induced Superconductivity and Structural Phase Transitions in Magnetic Topological Insulator Candidate MnSb4Te7

Abstract

The magnetic van der Waals crystals (MnX2Te4)m(X2Te3)n (X = Sb, Bi) have drawn significant attention due to their rich topological properties and the tenability by external magnetic field. In this work, we report on the discovery of superconductivity in magnetic topological insulator candidate MnSb4Te7 (m = 1, n = 1) via the application of high pressure. The antiferromagnetic ordering is robust to pressure until 8 GPa and then fully suppressed. The carrier type converts from hole- to electron-type accompanied with structural phase transition at around 15 GPa. Superconductivity emerges near the critical pressure 30 GPa where MnSb4Te7 converted into a simple cubic phase. Interestingly, MnSb4Te7 shows a dome-like phase diagram with a maximum Tc of 2.2 K at 50.7 GPa. The results demonstrate that MnSb4Te7 with nontrivial topology of electronic states display new ground states upon compression.

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Cuiying Pei, Ming Xi, Qi Wang, Wujun Shi, Lingling Gao, Yi Zhao, Shangjie Tian, Weizheng Cao, Changhua Li, Mingxin Zhang, Shihao Zhu, Yulin Chen, Hechang Lei, Yanpeng Qi. 2022-01-19. Pressure-Induced Superconductivity and Structural Phase Transitions in Magnetic Topological Insulator Candidate MnSb4Te7. https://arxiv.org/abs/2201.07635

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