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arXiv · 2401.16806

Vanadium-Doped Molybdenum Disulfide Monolayers with Tunable Electronic and Magnetic Properties: Do Vanadium-Vacancy Pairs Matter?

Da Zhou·Yen Thi Hai Pham·Diem Thi-Xuan Dang·David Sanchez·Aaryan Oberoi·Ke Wang·Andres Fest·Alexander Sredenschek·Mingzu Liu·Humberto Terrones·Saptarshi Das·Dai-Nam Le·Lilia M. Woods·Manh-Huong Phan·Mauricio Terrones
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Abstract

Monolayers of molybdenum disulfide (MoS2) are the most studied two-dimensional (2D) transition-metal dichalcogenides (TMDs), due to its exceptional optical, electronic, and opto-electronic properties. Recent studies have shown the possibility of incorporating a small amount of magnetic transition metals (e.g., Fe, Co, Mn, V) into MoS2 to form a 2D dilute magnetic semiconductor (2D-DMS). However, the origin of the observed ferromagnetism has remained elusive, due to the presence of randomly generated sulfur vacancies during synthesis that can pair with magnetic dopants to form complex dopant-vacancy configurations altering the magnetic order induced by the dopants. By combining high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) imaging with first-principles density functional theory (DFT) calculations and magnetometry data, we demonstrate the critical effects of sulfur vacancies and their pairings with vanadium atoms on the magnetic ordering in V-doped MoS2 (V-MoS2) monolayers. Additionally, we fabricated a series of field effect transistors on these V-MoS2 monolayers and observed the emergence of p-type behavior as the vanadium concentration increased. Our study sheds light on the origin of ferromagnetism in V-MoS2 monolayers and provides a foundation for future research on defect engineering to tune the electronic and magnetic properties of atomically thin TMD-based DMSs.

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Da Zhou, Yen Thi Hai Pham, Diem Thi-Xuan Dang, David Sanchez, Aaryan Oberoi, Ke Wang, Andres Fest, Alexander Sredenschek, Mingzu Liu, Humberto Terrones, Saptarshi Das, Dai-Nam Le, Lilia M. Woods, Manh-Huong Phan, Mauricio Terrones. 2024-01-30. Vanadium-Doped Molybdenum Disulfide Monolayers with Tunable Electronic and Magnetic Properties: Do Vanadium-Vacancy Pairs Matter?. https://arxiv.org/abs/2401.16806

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