Impact of Mn- and Fe-Doping on Electronic and Magnetic Properties of MoX₂ (<i>X</i> = S, Se) Monolayer
Neha Mishra, Bramha P. Pandey, Santosh Kumar
Abstract
In this study, the electronic and magnetic properties of Mn (Fe)-doped MoX <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${X}$ </tex-math></inline-formula> = S, Se) are extracted using first-principles calculations. Charge transfer (CT) and the total density of states are calculated as electronic properties. Magnetic moments (MMs), magnetic anisotropic energy (MAE), Curie temperature ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${T}_{c}$ </tex-math></inline-formula> ), and magnetic susceptibility ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$ {\chi }$ </tex-math></inline-formula> ) are obtained for magnetic properties. Doped systems exhibit significant changes in MM and CT. MAE is a critical parameter that arises because of spin-orbit coupling, exchange energy, and crystal field splitting in the proposed doped configurations, resulting in nondegeneracy. Furthermore, the MAE for Mn-doped MoS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> monolayer has a higher value of −8.46 meV with a negative sign, indicating preferred in-plane magnetization. In addition, for spin (down) states in Mn-MoS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (Fe-MoSe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) monolayers, the higher MM value is reflected. The lower Curie temperature of 4.42 K for Fe-doped MoSe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> monolayer later aligns it as a magnetic dilute semiconductor. The higher spin barrier height for spin (down) states (4.351 eV) of Mn-doped MoS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> monolayer determines the monolayer’s high spin-polarized current suitable for spintronic applications. As a result, compared to other Mn-MoSe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (Fe-MoS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> )-doped monolayer configurations, the Mn-MoS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (Fe-MoSe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) monolayer exhibits robust magnetic properties.