Controlled Curie temperature, magnetocrystalline anisotropy, and valley polarization in 2D ferromagnetic Janus 2H-VSeS monolayer

Abstract

Inspired by the successful synthesis of two-dimensional (2D) V-based Janus dichloride monolayers with intrinsic ferromagnetism and high Curie temperature (T${}_c$), the electronic structure, spin-valley splitting and magnetic anisotropy of Janus 2H-VSeS monolayers are investigated in detailed using first-principles calculations. The results show that the Janus 2H-VSeS monolayer exhibits a large valley splitting of 105meV, high T${}_c$ of 278K and good magnetocrystalline anisotropy (0.31meV) contributed by the in-plane d${}_{x^2-y^2}$/d${}_{xy}$ orbitals of V atoms. The biaxial strain ($-$8%<$\epsilon$<8%) can effectively tune the magnetic moments of V atom, valley splitting $\Delta$E, T${}_c$ and MAE of Janus 2H-VSeS monolayer. The corresponding $\Delta$E and T${}_c$ are adjusted from 72meV to 106.8meV and from 180K to 340K, respectively. The electronic phase transition from bipolar magnetic semiconductor (BMS) to half-semiconductor (HSC), spin gapless semiconductor (SGS), and half-metal (HM) is also observed due to the change of V 3d-orbital occupation. Due to the broken space- and time-reversal symmetry, the opposite valley charge carriers carry opposite Berry curvature, which leads to prominent anomalous Hall conductivity at the K and K${}^{\prime }$ valleys. The maximum modulation of Berry curvature can reach to 45% and 9.5% by applying the biaxial strain and charge carrier doping, respectively. The stable in-plane magnetocrystalline anisotropy and large spontaneous valley polarization make the ferromagnetic Janus 2H-VSeS monolayer a promising material for achieving the spintronics and valleytronics devices.

arXiv comment13 pages, 13 figures

References in corpus (16)

• Two-Dimensional Gas of Massless Dirac Fermions in Graphene
• VASPKIT: A User-friendly Interface Facilitating High-throughput Computing and Analysis Using VASP Code
• Layer-dependent Ferromagnetism in a van der Waals Crystal down to the Monolayer Limit
• Berry Phase Effects on Electronic Properties
• Wannier90: A Tool for Obtaining Maximally-Localised Wannier Functions
• Control of valley polarization in monolayer MoS2 by optical helicity
• Maximally localized Wannier functions: Theory and applications
• WannierTools: An open-source software package for novel topological materials
• Valley contrasting physics in graphene: magnetic moment and topological transport
• First Principles Calculation of Anomalous Hall Conductivity in Ferromagnetic bcc Fe
• Magnetic Control of Valley Pseudospin in Monolayer WSe2
• Very large Dzyaloshinskii-Moriya interaction in two-dimensional Janus manganese dichalcogenides and its application to realize skyrmion states
• Magnetic Skyrmion State in Janus Monolayers of Chromium Trihalides Cr(I,X)3
• VI3 - a new layered ferromagnetic semiconductor
• Intrinsic skyrmions in monolayer Janus magnets
• Valley-dependent spin transport in monolayer transition-metal dichalcogenides

Cited by in corpus (1)

• Transferable mechanism of perpendicular magnetic anisotropy switching by hole doping in V$X_2$ ($X$=Te, Se, S) monolayers