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

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 approximate to 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.

Automated summary

This study investigates semiconducting WSe2 monolayers doped with vanadium atoms, which exhibits p-type doping characteristics and impurity-related emission. Measurements on V-doped WSe2 devices show bipolar carrier tunability. The doped monolayers display magnetic hysteresis in transport measurements and a nonlinear g-factor for excitons without magnetic hysteresis. This work provides crucial insights regarding magnetic properties of doped 2D materials.