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arXiv · 2203.00817

Polaronic Conductivity in Cr$_2$Ge$_2$Te$_6$ Single Crystals

Yu Liu·Myung-Geun Han·Yongbin Lee·Michael O. Ogunbunmi·Qianheng Du·Christie Nelson·Zhixiang Hu·Eli Stavitski·David Graf·Klaus Attenkofer·Svilen Bobev·Liqin Ke·Yimei Zhu·C. Petrovic
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Abstract

Intrinsic, two-dimensional (2D) ferromagnetic semiconductors are an important class of materials for spin-charge conversion applications. Cr$_2$Ge$_2$Te$_6$ retains long-range magnetic order in bilayer at cryogenic temperatures and shows complex magnetic interactions with considerable magnetic anisotropy. Here, we performed a series of structural, magnetic, X-ray scattering, electronic, thermal transport and first-principles calculation studies which reveal that localized electronic charge carriers in Cr$_2$Ge$_2$Te$_6$ are dressed by surrounding lattice and are involved in polaronic transport via hopping that is sensitive on details of magnetocrystalline anisotropy. This opens possibility for manipulation of charge transport in Cr$_2$Ge$_2$Te$_6$ - based devices by electron-phonon- and spin-orbit coupling-based tailoring of polaron properties.

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Yu Liu, Myung-Geun Han, Yongbin Lee, Michael O. Ogunbunmi, Qianheng Du, Christie Nelson, Zhixiang Hu, Eli Stavitski, David Graf, Klaus Attenkofer, Svilen Bobev, Liqin Ke, Yimei Zhu, C. Petrovic. 2022-03-02. Polaronic Conductivity in Cr$_2$Ge$_2$Te$_6$ Single Crystals. https://doi.org/10.1002/adfm.202105111

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