Computational investigation of structural, magnetic, electronic and optical properties of the cluster Mn-X6 (X=P, S, Cl, Br or Te) doped monolayer WSe2

Abstract

• The Mn-S 6 doped monolayer WSe 2 under the W-rich condition is the most stable. • The Mn-S 6 , Mn-Cl 6 and Mn-Br 6 doped monolayer WSe 2 systems become magnetic half-metal. • The Mn-P 6 and Mn-Te 6 doped monolayer WSe 2 systems turn into magnetic semiconductor. • The Mn-X 6 doped monolayer WSe 2 systems exhibit red shift and enhanced absorption. We perform systematic first-principles calculations to clarify the effects of the cluster Mn-X 6 (X=P, S, Cl, Br or Te) doping on the structural, electronic, magnetic and optical properties of monolayer WSe 2 . The smaller formation energy shows that all doping systems are more stable under W-rich condition than Se-rich condition. The cluster Mn-S 6 doped monolayer WSe 2 has the smallest formation energy may be due to S and Se elements having similar electronegativity, while the maximum formation energy of the cluster Mn-Te 6 doping may be due to the lowest electronegativity of the Te element. Although pure monolayer WSe 2 is a non-magnetic semiconductor, the Mn-P 6 and Mn-Te 6 doped monolayer WSe 2 become magnetic semiconductor, while the Mn-S 6 , Mn-Cl 6 and Mn-Br 6 doped monolayer WSe 2 turn into magnetic half-metal. Compared with the pure monolayer WSe 2 , the cluster Mn-X 6 doped monolayer WSe 2 have not only a red-shift phenomenon but also an enhanced absorption in infrared and far-ultraviolet region and thus a potential application in infrared and far-ultraviolet light detectors.