Structure-dependent high-T_C ferromagnetism in Mn-doped GeSe

Abstract

Layered IV-VI diluted magnetic semiconductors (DMSs) have exhibited fascinating ferromagnetism down to atomic layers, but their relatively low Curie temperature (TC, ≤200 K) significantly hinders their practical application. In this...

Mn-X (X = F, Cl, Br, I) Co-Doped GeSe Monolayers: Stabilities and Electronic, Spintronic and Optical Properties

“…The calculated magnetic moments and spin charge density (∆ρ = ρ up − ρ down ) distributions in Figure 6 show that all the doped GeSe MLs are magnetic. Our results indicate that single doping of Mn results in a magnetic moment of 5.0 µB in (Ge, Mn) Se ML, which mainly comes from the spin-up electrons around Mn, consistent with previous theoretical results [16,17] and slightly larger than the 4.25 µB observed in GeMnSe nanocombs in previous experimental studies [35]. Mn-Cl and Mn-Br co-doping further weakened the magnetic moment to 4.0 µB in both cases by introducing more spin-down electrons in (Ge, Mn) (Se, Cl) and (Ge, Mn) (Se, Br) MLs.…”

Realization of the Tunable Multivalley System in a GeSe Monolayer by Atomic Substitution

“…Magnetic substrate, magnetic doping, and mixing are common methods for generating magnetism. − Magnetic atom-doping-induced magnetism in a GeSe monolayer is an effective method; especially, Mn atom doping can even produce ferromagnetism with Curie temperature T c up to 309 K in experiments. − However, in these examples, the substitution does not break the C 2 x symmetry operation; hence, it does not meet the condition. Interestingly, computational researches have shown that the substitution of Group V atoms (P, As, and Sb) for the Group IV Ge atom can induce structural distortion and break C 2 x symmetry operation while generating magnetism in the GeSe monolayer. − The reason can be attributed to the fact that Group V atoms have an extra electron compared to the Group IV Ge atom, and electron asymmetry leads to magnetic and structural distortions, which have been reported recently .…”

Recent advances in two-dimensional intrinsic ferromagnetic materials Fe3X(X=Ge and Ga)Te2 and their heterostructures for spintronics

“…2D magnets can provide novel opportunities for the development of spintronics. Very recently, large-scale 2D magnetic materials with above room-temperature ferromagnetism have been reported in Mn-doped GeSe films, 14 vacancy-incorporated MoSe 2 , 15 and strain-mediated MoS 2 16 and ReS 2 17 films, but their practical applications remain a challenge owing to limited controllability, which indicates that the investigation of 2D intrinsic magnets is imminent. The experimental findings of 2D vdW FM Cr 2 Ge 2 Te 6 , 11 CrI 3 18 and AFM FePS 3 19 with atomic layer thickness immediately lifted the curtain and triggered a wave of research on 2D vdW magnets.…”