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arXiv · 2412.03705

Long-lived population inversion in resonantly driven excitonic antiferromagnet

Jacob A. Warshauer·Huyongqing Chen·Daniel Alejandro Bustamante Lopez·Qishuo Tan·Jing Tang·Xi Ling·Wanzheng Hu
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Abstract

Van der Waals magnets are an emerging material family for investigating light-matter interactions and spin-correlated excitations. Here, we report the discovery of a photo-induced state with a lifetime of 17 ps in the van der Waals antiferromagnet NiPS$_3$, which appears exclusively with resonant pumping at 1.476 eV in the antiferromagnetic state. The long-lived state comes with a negative photoconductivity, a characteristic optical response of population inversion. Our findings demonstrate a promising pathway to potentially achieve long-lived lasing at terahertz frequencies in reduced dimensions.

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Jacob A. Warshauer, Huyongqing Chen, Daniel Alejandro Bustamante Lopez, Qishuo Tan, Jing Tang, Xi Ling, Wanzheng Hu. 2024-12-04. Long-lived population inversion in resonantly driven excitonic antiferromagnet. https://doi.org/10.1103/physrevlett.134.016901

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