Defect‐Engineered Magnetic Field Dependent Optoelectronics of Vanadium Doped Tungsten Diselenide Monolayers

Abstract The ability to dope transition metal dichalcogenides such as tungsten diselenide (WSe₂) with magnetic transition metal atoms in a controlled manner has motivated intense research with the aim of generating dilute magnetic semiconductors. In this work, semiconducting WSe₂ monolayers, substitutionally doped with vanadium atoms, are investigated using low‐temperature luminescence and optoelectronic spectroscopy. V‐dopants lead to a p‐type doping character and an impurity‐related emission ≈160 meV below the neutral exciton, both of which scale with the nominal percentage of V‐dopants. Measurements using field‐effect devices of 0.3% V‐doped WSe₂ demonstrate bipolar carrier tunability. The doped monolayers display a clear magnetic hysteresis in transport measurements both under illumination and without illumination, whereas the valley polarization of the excitons reveals a nonlinear g‐factor without a magnetic hysteresis within the experimental uncertainty. Hence, this work on V‐doped WSe₂ provides crucial insights concerning suitable characterization methods on magnetic properties of doped 2D materials.