Strain-dependent magnetic ordering switching in 2D AFM ternary V-based chalcogenide monolayers.

The lack of macroscopic magnetic moments makes antiferromagnetic materials promising candidates for high-speed spintronic devices. The 2D ternary V-based chalcogenides (VXYSe; X, Y = Al, Ga) monolayers are investigated based on the density-functional theory and Monte Carlo simulations. The results reveal that the Néel temperature of the VGaSe monolayer is 18 K with zigzag2-antiferromagnetic (AFM) spin ordering.

Ferroelectricity and High Curie Temperature in a 2D Janus Magnet.

The breaking of the out-of-plane symmetry makes a two-dimensional (2D) Janus monolayer a new platform to explore the coupling between ferroelectricity and ferromagnetism. Using density functional theory in combination with Monte Carlo simulations, we report a novel phase-switchable 2D multiferroic material VInSe with large intrinsic out-of-plane spontaneous electric polarization and a high Curie temperature (). The structural transition energy barrier between the two phases is determined to be 0.

Integrating ferromagnetism and ferroelectricity in an iron chalcogenide monolayer: a first-principles study.

Two-dimensional (2D) ferro-type materials have received great attention owing to the remarkable polarization effect in optoelectronics and spintronics. Using the first-principles method, the coupling between ferromagnetism and ferroelectricity is investigated in a multiferroic Janus 1T-FeSSe monolayer, which has a strong Stoner ferromagnetic ground state. The magnetic anisotropy energy (MAE) is apparently impacted by the out-of-plane asymmetry donated ferroelectricity, which is reflected by the asymmetry of the Z-MAE image.

PN/PAs-WSe van der Waals heterostructures for solar cell and photodetector.

By first-principles calculations, we investigate the geometric stability, electronic and optical properties of the type-II PN-WSe and type-I PAs-WSe van der Waals heterostructures(vdWH). They are p-type semiconductors with indirect band gaps of 1.09 eV and 1.

Modulation of the electronic band structure of silicene by polar two-dimensional substrates.

Using the density functional theory (DFT) calculations, we find that  Janus group-III chalcogenide monolayers can serve as a suitable substrate for silicene, and the Dirac electron band properties of silicene are also fully preserved. The maximum opened band gap can reach 179 meV at the Dirac point due to the interaction of silicene and the polar two-dimensional (2D) substrate. In addition, the electronic band structure of the heterostructure can be modulated by applying an electric field where its predicted band gap increases or decreases according to the direction of the applied external electric field.

Enhanced Shift Currents in Monolayer 2D GeS and SnS by Strain-Induced Band Gap Engineering.

Group IV monochalcogenides exhibit spontaneous polarization and ferroelectricity, which are important in photovoltaic materials. Since strain engineering plays an important role in ferroelectricity, in the present work, the effect of equibiaxial strain on the band structure and shift currents in monolayer two-dimensional (2D) GeS and SnS has systematically been investigated using the first-principles calculations. The conduction bands of those materials are more responsive to strain than the valence bands.

Perfect Spin Filtering in Homobimetallic Ni Complex with High Tolerance to Structural Changes.

In the theory of ligand fields, depending on the nature and field strength of the surrounding ligands, the central metal ion may exhibit different electronic configurations, low spin (LS) or high spin (HS). Realizing stable spin polarization is one of the main challenges in the field of molecular spintronic devices because of spin switching triggered by an external stimulus. Here, an asymmetric homobimetallic complex has been investigated using the nonequilibrium Green's function and spin density functional theory.