Tunable Electromagnetic Properties of the Porous Graphene‐Based Kagome Lattice

Strain-modulated electronic and magnetic properties of Co2TMAl

Strain engineering is a powerful technique for controlling the performance of semiconductor ceramic systems. In this article, the effect of strain engineering, specifically biaxial compressive and tensile strains, on the bonding characteristics, structure, electronic, and optical properties of nonplanar phosphorene‐like (NPP) ZnS ceramic nanolayers was investigated using density functional theory. It was observed that this ceramic exhibits greater stability under significant tensile strains. The structural stability of NPP‐ZnS ceramic, both with and without biaxial strain, was confirmed by its negative formation energy. Biaxial strain strongly influences the electronic band structure of NPP‐ZnS ceramic nanolayers, leading to a transformation from a direct band gap to an indirect gap under tensile strain. Additionally, the bandgap decreases under compressive strain, while it slightly increases under tensile strain. Various optical properties, including refractive index, extinction coefficient, absorption, reflectivity, optical conductivity, and optical susceptibility, were calculated. Biaxial compressive and tensile strains alter the optical properties, shifting them to higher or lower frequencies. NPP‐ZnS ceramic nanolayers exhibit high optical absorption in the UV range, which can be further enhanced by biaxial strain. Furthermore, under increasing compressive strain, the absorption edge moves toward higher energies. This improvement in optical absorption expands the potential applications of NPP‐ZnS ceramic nanolayers in optoelectronic devices.

Biaxial strain effects on electronic, transport, and thermoelectric properties of SnX[formula omitted] (X = Se, Te) and Janus SnSeTe 1T-monolayers

First principles calculations of La2O3/GaAs interface properties under biaxial strain and hydrostatic pressure

For semiconducting two-dimensional transition metal dichalcogenides (TMDs), the carrier transport properties of the material are affected by strain engineering. In this study, we investigate the carrier mobility of monolayer hafnium disulphide (HfS2) under different biaxial strains by first-principles calculations combined with the Kubo-Greenwood mobility approach and the compact band model. The decrease/increase in the effective mass of the conduction band (CB) of monolayer HfS2 caused by biaxial tensile/compressive strain is the major reason for the enhancement/degradation of its electron mobility. The lower hole effective mass of the valence bands (VB) in monolayer HfS2 under biaxial compressive strain improves its hole transport performance compared to that under biaxial tensile strain. In summary, biaxial compressive strain causes a decrease in both the effective mass and phonon scattering rate of monolayer HfS2, resulting in an increase in its carrier mobility. Under the biaxial compressive strain reaches 4%, the electron mobility enhancement ratio of the CB of monolayer HfS2 is ~90%. For the VB of monolayer HfS2, the maximum hole mobility enhancement ratio appears to be ~13% at a biaxial compressive strain of 4%. Our results indicate that the carrier transport performance of monolayer HfS2 can be greatly improved by strain engineering.

For semiconducting two-dimensional transition metal dichalcogenides, carrier transport proper-ties of the material are affected by strain engineering. In this work, we investigate the carrier mo-bility of monolayer hafnium disulphide (HfS2) under different biaxial strains by first-principles calculations combined with Kubo-Greenwood mobility approach and compact band model. The decrease/increase in effective mass of conduction band of monolayer HfS2 caused by biaxial ten-sile/compressive strain is the major reason for the enhancement/degradation of its electron mobil-ity. Lower hole effective mass of valence bands in the monolayer HfS2 under biaxial compressive strain results in the better hole transport performance of monolayer HfS2 than the one with biaxial tensile strain. In summary, biaxial compressive strain decreases both effective mass and phonon scattering rate of monolayer HfS2, resulting in an increase in carrier mobility. When the biaxial compressive strain reaches 4%, for the conduction band of monolayer HfS2, electron mobility en-hancement ratio is ~90%. For the valence band of monolayer HfS2, the maximum hole mobility enhancement ratio appears ~13% at biaxial compressive strain of 4%. Our results indicate that the carrier transport performance of monolayer HfS2 can be greatly improved by the strain engineer-ing.

The electronic properties of two-dimensional monolayer and bilayer phosphorene subjected to uniaxial and biaxial strains have been investigated using first-principles calculations based on density functional theory. Strain engineering has obvious influence on the electronic properties of monolayer and bilayer phosphorene. By comparison, we find that biaxial strain is more effective in tuning the band gap than uniaxial strain. Interestingly, we observe the emergence of Dirac-like cones by the application of zigzag tensile strain in the monolayer and bilayer systems. For bilayer phosphorene, we induce the anisotropic Dirac-like dispersion by the application of appropriate armchair or biaxial compressive strain. Our results present very interesting possibilities for engineering the electronic properties of phosphorene and pave a way for tuning the band gap of future electronic and optoelectronic devices.

Strain engineering for optimized hydrogen storage: Enhancing ionic conductivity and achieving near-room-temperature desorption in Mg₂NiH₄

Advances in strain engineering on oxide heteroepitaxy

In the present work, we consider the electronic properties of bulk and single-layer InSe using the density functional theory. Our calculations show that at the equilibrium state, the single-layer InSe is a semiconductor with an indirect energy bandgap of 1.382 1 eV, nearly twice the bandgap of bulk InSe. Focusing on the effect of biaxial strain εb on electronic properties of single-layer InSe, our calculated results indicate that tensile biaxial strain changes slightly the valence subbands near Fermi level, while the band structure of the single-layer InSe depends tightly on the compressive biaxial strain. Also, the energy gap of the single-layer InSe depends almost linearly on the εb. However, the energy gap tends to increase slowly when the large compressive biaxial strain is applied. We believe that the control of the energy gap of the single-layer InSe by strain engineering can be useful in its application in nanoelectromechanical systems and nanoelectronic devices.

Spin-gapless semiconductors (SGSs), with intrinsic magnetism, $100%$ spin polarization, and zero-gap band crossing points, have attracted great scientific interest owing to their potential applications in spintronics. In this Letter, using first-principles calculations and symmetry analysis, we demonstrate that the realistic material ${\mathrm{Sr}}_{2}{\mathrm{CuF}}_{6}$ is a spintronic material with multiple dimensions of spin-gapless semiconducting states. Tetragonal ${\mathrm{Sr}}_{2}{\mathrm{CuF}}_{6}$ has a zero-dimensional zero-gap nodal point, a one-dimensional zero-gap nodal line, and a two-dimensional nearly zero-gap nodal surface in one spin direction. Moreover, it hosts a wide band gap in the other spin direction. Our results extend the SGS members from nodal point SGSs and nodal line SGSs to nodal surface SGSs. Furthermore, we report a SGS candidate in an experimentally realized material exhibiting different dimensions of zero-gap points in momentum space. It is hoped that spintronic materials with multiple dimensions of spin-gapless semiconducting states may have significant applications in new-generation spintronics.

The electronic properties of single/bi-layer SnSe are theoretically studied using first-principles approach based on density-functional theory (DFT). The band structure and lattice parameters are researched. In order to gain more desirable electronic property, the in-plane strain and external electric field are adopted to modulate their electronic properties. The simulation results demonstrate that no matter biaxial or uniaxial strain, the bilayer structure shows a better linearity character, but for armchair direction, the monolayer SnSe would receive a larger band gap tuning range. The biaxial strain also can induce indirect-direct band gap transformation. The electronic field Therefore, we suggest the tunable electronic property SnSe can be used as a strain or other application sensors.

Research on two-dimensional magnetic materials has gained significant attention in recent years owing to their unique thickness-dependent magnetism, tunable properties, and potential applications in spintronics, quantum computing, and next-generation data storage technologies. This study investigated the intrinsic ferromagnetic (FM) properties of Cr2X4Y (X = S, Se; Y = Ga, Ge, In, Sn) monolayers, with emphasis on their potential application in spintronic devices. Comprehensive stability analyses confirmed the feasibility of synthesizing these materials. Our results predict that all of these materials would exhibit robust ferromagnetism with magnetic moments of ∼4 µ B per Cr atom and high Curie temperatures ( T c ) ranging from 170 K to 691 K, with Cr2S4Ga achieving the highest T c . The FM behavior, attributed to superexchange interactions, remains stable under biaxial strain (−6% to 6%). Based on their electronic structures, half-metallicity is predicted for Cr2X4Y (Y = Ga, In), which enables 100% spin polarization, whereas Cr2X4Y (Y = Ge, Sn) are semiconductors with sizable band gaps. These findings indicate that the Cr2X4Y monolayers are promising candidates for room-temperature spintronic devices with tunable magnetic properties.

Biaxial versus uniaxial strain tuning of single-layer MoS2

Feeling the strain: Enhancing the thermodynamics characteristics of magnesium nickel hydride Mg2NiH4 for hydrogen storage applications through strain engineering