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arXiv · 2203.00675

Visualizing the out-of-plane electronic dispersions in an intercalated transition metal dichalcogenide

Xian P. Yang·Harrison LaBollita·Zi-Jia Cheng·Hari Bhandari·Tyler A. Cochran·Jia-Xin Yin·Md. Shafayat Hossain·Ilya Belopolski·Qi Zhang·Yuxiao Jiang·Nana Shumiya·Daniel Multer·Maksim Liskevich·Dmitry A. Usanov·Yanliu Dang·Vladimir N. Strocov·Albert V. Davydov·Nirmal J. Ghimire·Antia S. Botana·M. Zahid Hasan
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Abstract

Layered transition metal dichalcogenides have rich phase diagram and they feature two dimensionality on numerous physical properties. Co1/3NbS2 is one of the newest members of this family where Co atoms are intercalated into the Van der Waals gaps between NbS2 layers. We study the three-dimensional electronic band structure of Co1/3NbS2 using both surface and bulk sensitive angle-resolved photoemission spectroscopy. We show that the electronic bands do not fit into the rigid-band-shift picture after the Co intercalation. Instead, Co1/3NbS2 displays a different orbital character near the Fermi level compared to the pristine NbS2 compound and has a clear band dispersion in kz direction despite its layered structure. Our photoemission study demonstrates the out-of-plane electronic correlations introduced by the Co intercalation, thus offering a new perspective on this compound. Finally, we propose how Fermi level tuning could lead to exotic phases such as spin density wave instability.

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Xian P. Yang, Harrison LaBollita, Zi-Jia Cheng, Hari Bhandari, Tyler A. Cochran, Jia-Xin Yin, Md. Shafayat Hossain, Ilya Belopolski, Qi Zhang, Yuxiao Jiang, Nana Shumiya, Daniel Multer, Maksim Liskevich, Dmitry A. Usanov, Yanliu Dang, Vladimir N. Strocov, Albert V. Davydov, Nirmal J. Ghimire, Antia S. Botana, M. Zahid Hasan. 2022-03-01. Visualizing the out-of-plane electronic dispersions in an intercalated transition metal dichalcogenide. https://doi.org/10.1103/physrevb.105.l121107

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