  The electronic and magnetic properties of cobalt (Co) doped monolayer (ML)
tungsten diselenide (WSe2) are investigated using the density functional theory
with the on-site Hubbard potential correction (DFT+U) for the localized d
orbitals of Co atom taking into account the spin orbit coupling (SOC)
interaction. The results show that the substitution of Co at the W sites of ML
WSe2 is energetically favorable under Se rich environment. We noticed that the
Hund's exchange splitting (\Delta H_{ex}) is dominant over the crystal field
splitting (\Delta_{cf}). The induced magnetic moment due to the Co-doped defect
is ~3.00 \mu_B per Co atom. The magnetic interaction between two Co atoms at
the nearest neighbor separation depends mainly on the concentration of the
impurity atoms. The calculated value of curie temperature (TC) is increasing
with increasing impurity concentration satisfying the Zener model. Based on the
results, it can be proposed that the Co-doped WSe2 monolayer is potential
candidate to apply in spintronics, optoelectronics, and magnetic storage
devices.
