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arXiv · 2505.22559

Observation of Coherent Ferron Emission and Propagation

Jeongheon Choe·Taketo Handa·Chun-Ying Huang·André Koch Liston·Jordan Cox·Jonathan Stensberg·Yongseok Hong·Daniel G. Chica·Ding Xu·Fuyang Tay·Samra Husremovic·Vinicius da Silveira Lanza Avelar·Eric A. Arsenault·Zhuquan Zhang·James McIver·Dmitri N. Basov·Milan Delor·Xavier Roy·X. -Y. Zhu
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Abstract

Excitation of ordered quantum phases gives rise to collective modes and quasiparticles, as exemplified by spin waves and magnons emerging from magnetic order. Extending this paradigm to ferroelectric materials suggests the existence of polarization waves and their fundamental quanta, ferrons. Here, we report the generation and transport of polarization waves, i.e., coherent ferrons, in the van der Waals ferroelectric material NbOI2. Upon excitation by a short laser pulse, the polarization wave emits intense and narrow-band terahertz (THz) radiation at the ferroelectric transverse optical phonon frequency, modulates the ferroelectric order parameter, and propagates uniaxially along the polar axis at hypersonic velocities of ~105 m/s. These long-lived, uniaxial, and dipole-carrying polarization waves may find applications in narrow-band THz emission, ferronic information processing, and coherent electric control.

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BibTeXRIS

Jeongheon Choe, Taketo Handa, Chun-Ying Huang, André Koch Liston, Jordan Cox, Jonathan Stensberg, Yongseok Hong, Daniel G. Chica, Ding Xu, Fuyang Tay, Samra Husremovic, Vinicius da Silveira Lanza Avelar, Eric A. Arsenault, Zhuquan Zhang, James McIver, Dmitri N. Basov, Milan Delor, Xavier Roy, X. -Y. Zhu. 2025-05-28. Observation of Coherent Ferron Emission and Propagation. https://doi.org/10.1038/s41563-026-02597-4

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