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The capacity to manipulate magnetization in 2D dilute magnetic semiconductors (2D‐DMSs) using light, specifically in magnetically doped transition metal dichalcogenide (TMD) monolayers (M‐dopedTX₂, whereM = V, Fe, and Cr;T = W, Mo;X = S, Se, and Te), may lead to innovative applications in spintronics, spin‐caloritronics, valleytronics, and quantum computation. This Perspective paper explores the mediation of magnetization by light under ambient conditions in 2D‐TMD DMSs and heterostructures. By combining magneto‐LC resonance (MLCR) experiments with density functional theory (DFT) calculations, we show that the magnetization can be enhanced using light in V‐doped TMD monolayers (e.g., V‐WS₂, V‐WSe₂). This phenomenon is attributed to excess holes in the conduction and valence bands, and carriers trapped in magnetic doping states, mediating the magnetization of the semiconducting layer. In 2D‐TMD heterostructures (VSe₂/WS₂, VSe₂/MoS₂), the significance of proximity, charge‐transfer, and confinement effects in amplifying light‐mediated magnetism is demonstrated. We attributed this to photon absorption at the TMD layer that generates electron–hole pairs mediating the magnetization of the heterostructure. These findings will encourage further research in the field of 2D magnetism and establish a novel design of 2D‐TMDs and heterostructures with optically tunable magnetic functionalities, paving the way for next‐generation magneto‐optic nanodevices.

The field of photovoltaics is revolutionized in recent years by the development of two–dimensional (2D) type‐II heterostructures. These heterostructures are made up of two different materials with different electronic properties, which allows for the capture of a broader spectrum of solar energy than traditional photovoltaic devices. In this study, the potential of vanadium (V)‐doped WS₂is investigated, hereafter labeled V‐WS₂, in combination with air‐stable Bi₂O₂Se for use in high‐performance photovoltaic devices. Various techniques are used to confirm the charge transfer of these heterostructures, including photoluminescence (PL) and Raman spectroscopy, along with Kelvin probe force microscopy (KPFM). The results show that the PL is quenched by 40%, 95%, and 97% for WS₂/Bi₂O₂Se, 0.4 at.% V‐WS₂/Bi₂O₂Se, and 2 at.% V‐WS₂/Bi₂O₂Se, respectively, indicating a superior charge transfer in V‐WS₂/Bi₂O₂Se compared to pristine WS₂/Bi₂O₂Se. The exciton binding energies for WS₂/Bi₂O₂Se, 0.4 at.% V‐WS₂/Bi₂O₂Se and 2 at.% V‐WS₂/Bi₂O₂Se heterostructures are estimated to be ≈130, 100, and 80 meV, respectively, which is much lower than that for monolayer WS₂. These findings confirm that by incorporating V‐doped WS₂, charge transfer in WS₂/Bi₂O₂Se heterostructures can be tuned, providing a novel light‐harvesting technique for the development of the next generation of photovoltaic devices based on V‐doped transition metal dichalcogenides (TMDCs)/Bi₂O₂Se.

The ability to control the density and spatial distribution of substitutional dopants in semiconductors is crucial for achieving desired physicochemical properties. Substitutional doping with adjustable doping levels has been previously demonstrated in 2D transition metal dichalcogenides (TMDs); however, the spatial control of dopant distribution remains an open field. In this work, edge termination is demonstrated as an important characteristic of 2D TMD monocrystals that affects the distribution of substitutional dopants. Particularly, in chemical vapor deposition (CVD)‐grown monolayer WS₂, it is found that a higher density of transition metal dopants is always incorporated in sulfur‐terminated domains when compared to tungsten‐terminated domains. Two representative examples demonstrate this spatial distribution control, including hexagonal iron‐ and vanadium‐doped WS₂monolayers. Density functional theory (DFT) calculations are further performed, indicating that the edge‐dependent dopant distribution is due to a strong binding of tungsten atoms at tungsten‐zigzag edges, resulting in the formation of open sites at sulfur‐zigzag edges that enable preferential dopant incorporation. Based on these results, it is envisioned that edge termination in crystalline TMD monolayers can be utilized as a novel and effective knob for engineering the spatial distribution of substitutional dopants, leading to in‐plane hetero‐/multi‐junctions that display fascinating electronic, optoelectronic, and magnetic properties.

Dilute magnetic semiconductors (DMS), 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 (2D) 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, 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, is described. These monolayers develop p‐type transport as a function of vanadium incorporation and rapidly reach ambipolarity. Ferromagnetism peaks at an intermediate vanadium concentration of ~2 at% 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 2D‐DMS provide a new component to expand the functional scope of van der Waals heterostructures and bring semiconducting magnetic 2D heterostructures into the realm of practical application.