Tuning magnetism of monolayer MoS2 by doping vacancy and applying strain

Abstract

In view of important role of inducing and manipulating the magnetism in two-dimensional materials for the development of low-dimensional spintronic devices, the influences of strain on electronic structure and magnetic properties of commonly observed vacancies doped monolayer MoS2 are investigated using first-principles calculations. It is shown that unstrained VS, VS2, and VMoS3 doped monolayer MoS2 systems are nonmagnetic, while the ground state of unstrained VMoS6 doped system is magnetic and the magnetic moment is contributed mainly by six Mo atoms around VMoS6. In particular, tensile strain can induce magnetic moments in VS, VS2, and VMoS3 doped monolayer MoS2 due to the breaking of Mo–Mo metallic bonds around the vacancies, while the magnetization induced by VMoS6 can be effectively manipulated by equibiaxial strain due to the change of Mo–Mo metallic bonds around VMoS6 under strains.

Magnetism of Ta dichalcogenide monolayers tuned by strain and hydrogenation

“…This research is exemplified by calculations of the magnetic moment for different chemical compositions 20 and of straininduced magnetism. [23][24][25] Some of the published information is contradictory such as the reports of strain-dependent ferromagnetism 26 and antiferromagnetism 27 in NbX 2 (X ¼ S, Se) monolayers.…”

“…14 The properties of 2D TMDs vary from semiconducting (MoS 2 , WS 2 ) to metallic (NbSe 2 , TaS 2 ) and magnetic (VS 2 , VSe 2 ). [15][16][17][18] Very recently, it has become clear that 2D TMDs exhibit striking physical-property changes due to strain, 14,[19][20][21][22][23][24][25][26][27] chemical functionalization, [28][29][30][31][32][33] doping with transition metals, 34 and external electric fields. 35 For instance, it has been demonstrated experimentally that strain modulates the bandgap of monolayers and bilayers in MoS 2 .…”

Effects of line defects on spin-dependent electronic transport of zigzag MoS2 nanoribbons

“…23 Zheng et al predicted by first-principles calculations that macroscopic ferromagnetism of MoS 2 nanosheets could be introduced by applying doping vacancy defects. 24 Cai et al found that the transformation of the surrounding 2H-MoS 2 local lattice into a trigonal MoS 2 could be prompted if introducing S vacancy in a 2H-MoS 2 ultrathin nanosheet host. Then, a robust intrinsic ferromagnetic response may be created.…”

Investigation of electron irradiation-induced magnetism in layered MoS2 single crystals

“…Additionally, the large magnetic moments and HRTEM image (Fig. S8, supplementary material) of the H(i) sample suggest that the non-magnetic V S2 -like defects 30 are much similar to the electron beaminduced 1 T phase 20 because the 1 T-phase incorporated MoS 2 samples via the chemical method induced the magnetism. 17,25 This may be a more simple way than a two-step hydrothermal method to intentionally introduce V S defects, which transform the local lattice surrounding the V S into 1 T phase.…”

“…21,23 Meanwhile, the theoretical study has reported that while the V S , V S2 , and V MoS3 vacancies doped monolayer MoS 2 systems are nonmagnetic, the tensile strain induces magnetic moments in these systems by breaking of Mo-Mo metallic bonds around the vacancies. 30 In fact, the distances between the two neighboring Mo atoms around such vacancies increase in the electron irradiated samples compared to the distance (a ¼ 3.12 Å ) 26 of the pristine MoS 2 (Figs. S6-S10, supplementary material).…”