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arXiv · 2411.10756

Ultrafast photoinduced phase transition in the antiferromagnetic Dirac semimetal EuAgAs

Hao Liu·Chen Zhang·Qi-Yi Wu·Yahui Jin·Ziming Zhu·Jiao-Jiao Song·Sheng-Tao Cui·Zhe Sun·Honghong Wang·Bo Chen·Jun He·Hai-Yun Liu·Yu-Xia Duan·Peter M. Oppeneer·Jian-Qiao Meng
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Abstract

We report the observation of a light-induced subpicosecond phase transition in the antiferromagnetic Dirac semimetal EuAgAs, achieved through ultrafast optical excitation. Using ultrafast optical spectroscopy, we probe the nonequilibrium carrier dynamics, discovering distinct fluence-dependent responses in the antiferromagnetic and paramagnetic states, and revealing a possible magnetic order-driven transition between different topological states. Our results demonstrate that EuAgAs, with its highly tunable magnetic structure, possibly offers a unique platform for exploring topological phase transitions. These results underscore the potential of ultrashort optical pulses as powerful tools for the real-time control of topological phases, opening pathways for advances in spintronics, quantum computing, and energy-efficient information technologies.

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Hao Liu, Chen Zhang, Qi-Yi Wu, Yahui Jin, Ziming Zhu, Jiao-Jiao Song, Sheng-Tao Cui, Zhe Sun, Honghong Wang, Bo Chen, Jun He, Hai-Yun Liu, Yu-Xia Duan, Peter M. Oppeneer, Jian-Qiao Meng. 2024-11-16. Ultrafast photoinduced phase transition in the antiferromagnetic Dirac semimetal EuAgAs. https://doi.org/10.1103/physrevb.111.l121113

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