Temperature-sensitive spatial distribution of defects in PdSe2 flakes

Xiaowei Liu; Yaojia Wang; Qiqi Guo; Shijun Liang; Tao Xu; Bo Liu; Jiabin Qiao; Shengqiang Lai; Junwen Zeng; Song Hao; Chenyi Gu; Tianjun Cao; Chenyu Wang; Yu Wang; Chen Pan; Guangxu Su; Yuefeng Nie; Xiangang Wan; Litao Sun; Zhenlin Wang; Lin He; Bin Cheng; Feng Miao

arXiv · 2104.06642

Temperature-sensitive spatial distribution of defects in PdSe2 flakes

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Abstract

Defect engineering plays an important role in tailoring the electronic transport properties of van der Waals materials. However, it is usually achieved through tuning the type and concentration of defects, rather than dynamically reconfiguring their spatial distribution. Here, we report temperature-sensitive spatial redistribution of defects in PdSe2 thin flakes through scanning tunneling microscopy (STM). We observe that the spatial distribution of Se vacancies in PdSe2 flakes exhibits a strong anisotropic characteristic at 80 K, and that this orientation-dependent feature is weakened when temperature is raised. Moreover, we carry out transport measurements on PdSe2 thin flakes and show that the anisotropic features of carrier mobility and phase coherent length are also sensitive to temperature. Combining with theoretical analysis, we conclude that temperature-driven defect spatial redistribution could interpret the temperature-sensitive electrical transport behaviors in PdSe2 thin flakes. Our work highlights that engineering spatial distribution of defects in the van der Waals materials, which has been overlooked before, may open up a new avenue to tailor the physical properties of materials and explore new device functionalities.

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Xiaowei Liu, Yaojia Wang, Qiqi Guo, Shijun Liang, Tao Xu, Bo Liu, Jiabin Qiao, Shengqiang Lai, Junwen Zeng, Song Hao, Chenyi Gu, Tianjun Cao, Chenyu Wang, Yu Wang, Chen Pan, Guangxu Su, Yuefeng Nie, Xiangang Wan, Litao Sun, Zhenlin Wang, Lin He, Bin Cheng, Feng Miao. 2021-04-14. Temperature-sensitive spatial distribution of defects in PdSe2 flakes. https://arxiv.org/abs/2104.06642

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