Monolayer Vanadium-doped Tungsten Disulfide: A Room-Temperature Dilute Magnetic Semiconductor

Fu Zhang; Boyang Zheng; Amritanand Sebastian; Hans Olson; Mingzu Liu; Kazunori Fujisawa; Yen Thi Hai Pham; Valery Ortiz Jimenez; Vijaysankar Kalappattil; Leixin Miao; Tianyi Zhang; Rahul Pendurthi; Yu Lei; Ana Laura Elías; Yuanxi Wang; Nasim Alem; Patrick E. Hopkins; Saptarshi Das; Vincent H. Crespi; Manh-Huong Phan; Mauricio Terrones

arXiv · 2005.01965

Monolayer Vanadium-doped Tungsten Disulfide: A Room-Temperature Dilute Magnetic Semiconductor

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Abstract

Dilute magnetic semiconductors, achieved through substitutional doping of spin-polarized transition metals into semiconducting systems, enable experimental modulation of spin dynamics in ways that hold great promise for novel magneto-electric or magneto-optical devices, especially for two-dimensional systems such as transition metal dichalcogenides that accentuate interactions and activate valley degrees of freedom. Practical applications of 2D magnetism will likely require room-temperature operation, air stability, and (for magnetic semiconductors) the ability to achieve optimal doping levels without dopant aggregation. Here we describe room-temperature ferromagnetic order obtained in semiconducting vanadium-doped tungsten disulfide monolayers produced by a reliable single-step film sulfidation method across an exceptionally wide range of vanadium concentrations, up to 12 at% with minimal dopant aggregation. These monolayers develop p-type transport as a function of vanadium incorporation and rapidly reach ambipolarity. Ferromagnetism peaks at an intermediate vanadium concentration of a few atomic percent and decreases for higher concentrations, which is consistent with quenching due to orbital hybridization at closer vanadium-vanadium spacings, as supported by transmission electron microscopy, magnetometry and first-principles calculations. Room-temperature two-dimensional dilute magnetic semiconductors provide a new component to expand the functional scope of van der Waals heterostructures and bring semiconducting magnetic 2D heterostructures them into the realm of practical application.

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Fu Zhang, Boyang Zheng, Amritanand Sebastian, Hans Olson, Mingzu Liu, Kazunori Fujisawa, Yen Thi Hai Pham, Valery Ortiz Jimenez, Vijaysankar Kalappattil, Leixin Miao, Tianyi Zhang, Rahul Pendurthi, Yu Lei, Ana Laura Elías, Yuanxi Wang, Nasim Alem, Patrick E. Hopkins, Saptarshi Das, Vincent H. Crespi, Manh-Huong Phan, Mauricio Terrones. 2020-05-05. Monolayer Vanadium-doped Tungsten Disulfide: A Room-Temperature Dilute Magnetic Semiconductor. https://arxiv.org/abs/2005.01965

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