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The suitability of halide-based double perovskites for implementation in infrared detectors and thermoelectric devices arises from their inherent environmental stability, non-toxic nature, and demonstrable performance. In the present investigation, our focus centers on an exploration of the structural stability and mechanical attributes intrinsic in Na2CuInY6 (Y = Cl, Br, I) within its cubic phase utilizing DFT. The structural and thermodynamic stability is investigated by computation of tolerance factor and enthalpy of formation. Our methodology encompasses comprehensive calculations of elastic constants based on Born stability criteria that help to understand the mechanical behavior and ductile nature of these compositions. Notably, our scrutiny of the electronic band structure reveals the presence of a direct semiconducting bandgap ranging between 1.30 and 0.36 eV. This distinctive feature holds a pivotal role in facilitating optoelectronic applications because of its pronounced role in absorption within the infrared spectrum. Remarkably, our investigation into the dielectric constant allows us to pinpoint the region of maximal light absorption within the visible spectrum. Lastly, using the BoltzTraP package, we computed the thermoelectric properties of the material and noticed an almost constant value of ZT in the wide range of temperatures highlighting the large range of workability of these compositions for thermoelectric device applications. [ABSTRACT FROM AUTHOR]

This study aimed to comprehensively investigate the optoelectronic and magnetic properties of Mo, Zn/LiNbO3 (1 1 1) material. The primary objectives were to understand the potential for manipulating the material's magnetism and to elucidate the origin of spin‐polarized states and magnetic moments, particularly with respect to the unpaired d orbitals of Nb, Mo, and Zn atoms. To achieve these objectives, we employed the Pardew–Burke–Ernzerhof (PBE) method within the Generalized Gradient Approximation (GGA + U) framework. This computational approach allowed us to examine the optoelectronic and magnetic characteristics of the material in detail. Our research yielded several key findings that enhance our understanding of Mo, Zn/LiNbO3 (1 1 1) material. We observed a modest improvement in the material's absorption capacity within the visible spectrum, accompanied by a discernible red‐shift. Notably, our study involved the calculation of the dielectric function and refractive constant of the material, revealing a strong correlation between absorption trends and the dielectric constant. Furthermore, our investigation uncovered that Mo, Zn/LiNbO3 (1 1 1) exhibits distinct conduction and valence bands, with p and d orbitals predominantly contributing to each, respectively. The energy gap of the material falls within a range of 0.30–1.04 eV. A particularly significant finding was the narrower band gap of Mo, Zn/LiNbO3 (1 1 1) material, which can be attributed to the superposition of Mo‐d and Zn‐p orbit energy levels with O‐p orbit energy levels, ultimately forming a covalent bond. Importantly, our research demonstrated the material's heightened optical absorption within the visible spectrum, suggesting its suitability for various photonic and optoelectronic applications. Additionally, we calculated a wide range of optical characteristics, including the dielectric function, absorption coefficient, energy loss, reflectivity, refractive index, extinction coefficient, and optical conductivity, providing a comprehensive assessment of the material's optical properties. [ABSTRACT FROM AUTHOR]

Herein, the electronic and magnetic properties of the 2D Janus monolayer VSeTe are computed based on first‐principles calculations. The structure stability plays a crucial role in real application for magnetic devices; it is found that the VSeTe favors 2H structure due to non‐negative frequencies in the phonon spectra. The VSeTe monolayer possesses a semiconductor nature with a bandgap of 1.03 eV (0.85 eV) for spin‐up (down) channels. Interestingly, it is shown in the computed results that VSeTe monolayer is a magnetic semiconductor with a magnetic moment of 1.00 μB$\left(\mu\right)_{\text{B}}$. Additionally, the realization of magnetic anisotropy energy can pave the way to utilize VSeTe monolayer for applications in magnetic semiconductor devices. [ABSTRACT FROM AUTHOR]

Herein, a comprehensive theoretical analysis of Tm‐based chalcogenides MgTm2Y4 (Y = S, Se) is performed to understand magnetic, optical, mechanical, and transport characteristics. And, Perdew–Burke–Ernzerhof generalized gradient approximation (PBEsol‐GGA) functional and modified Becke–Johnson (mBJ) potentials are employed while computing the mechanical and spin‐polarized electronic properties, respectively. The structural stability of both spinels is confirmed using formation energy and Born stability criteria. Both spinels are found exhibiting ductile nature according to the computed Pugh's and Poisson's ratios. For observing the room‐temperature ferromagnetism, Curie temperature is calculated. Furthermore, spin‐polarized electronic properties reveal that both spinels exhibit ferromagnetic nature, which is induced due to coupling among Tm‐ and S/Se‐related constituent states. The potential optoelectronic applications are suggested by computing and discussing dielectric constant, refractive index, and absorption coefficient. BoltzTraP code is used to investigate the thermoelectric features of MgTm2Y4 (Y = S, Se) in the 200–800 K temperature range. [ABSTRACT FROM AUTHOR]

Using density functional theory, the electronic and optical properties of monolayer platinum dichalcogenides (PtX2) are calculated. It is observed that PtS2, PtSe2, and PtTe2 have indirect bandgap of 2.70, 1.94, and 0.82 eV, respectively, indicating their potential in light harvesting. According to the calculated absorption spectra, PtX2 (X = S, Se, Te) absorbs the light extremely well in the visible range (300–700 nm), implying potential as third‐generation solar absorber in tandem configuration. The calculated device absorption efficiency increases above 90% at smaller wavelengths (300–350 nm). As a result, strong absorption across the entire light spectrum, from visible to UV, is exhibited. Interestingly, the top cell in tandem architecture requires a wider bandgap and strong device absorption efficiency, and these conditions are perfectly fulfilled by the materials PtS2 and PtSe2. The narrower gap (0.82 eV) and strong absorption of PtTe2 make it an excellent candidate for bottom cell in tandem architecture. Furthermore, it is observed that PtX2 family is useful for oxidizing H2O into O2 but fails to reduce H+ to H2. Thus, suitable bandgap, photocatalytic property for splitting water, and strong absorption efficiency make PtX2 an efficient candidate for application in optoelectronic devices, photocatalysis, and solar cells. [ABSTRACT FROM AUTHOR]

This paper is motivated to study the weak gravitational lensing of the black hole in the context of Starobinsky–Bel–Robinsion gravity. We deduce the deflection angle of light in the weak field limits. For this purpose, we find the Gaussian curvature and apply the Gauss–Bonnet theorem. We also investigate the deflection angle at which light is deflected by a plasma medium. Furthermore, we analyze the graphical behavior of the deflection angle in the framework of SBR gravity. We also calculate the energy extracted from the black hole in SBR gravity, Einstein ring, and lens equation in the non-plasma and plasma framework. We conclude this study with a discussion of how light beams behave when they approach such a four-dimensional black hole by calculating the deflection angle. [ABSTRACT FROM AUTHOR]

The mechanical, thermal and dynamical stabilities, electronic structure, contact type, and height of the barrier at the interface of TaX 2 (X = S, Se, Te) and BY (Y = P, As, Sb) metal-semiconductor (MS) contact are investigated via first principles calculations. Binding energies, mechanical properties, phonon spectra and ab initio molecular dynamics (AIMD) simulations confirm the stabilities of these systems. TaX 2 -BY (X = S, Se, Te; Y = P, As, Sb) MS van der Waals heterostructures (vdWHs) are found to be metal with a Schottky contact at the interface. Formation of the n-type Schottky contact at the interface of TaX 2 -BY (X = S, Se, Te; Y = P, As, Sb) MS vdWHs favors electron conduction over hole conduction. Small (higher) effective mass (carrier mobility) make TaS 2 -BSb, TaSe 2 -BSb and TaTe 2 -BSb MS vdWHs, potential candidates for high speed nanoelectronic applications. Bader charge analysis shows that at the interface of TaX 2 -BY (X = S, Se, Te; Y = P, As, Sb) MS vdWHs, in TaX 2 (BP, BAs) the electrons transfer from the TaX 2 layer to the BP and BAs layer, while in TaX 2 (BSb) the electrons transfer from the BSb layer to TaX 2 layer., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In this paper, we use density functional theory (DFT) using full-potential linearized augmented plan wave plus local orbital method (FP-LAPW + lo). The structural, electronic, optical, photocatalytic, mechanical, vibrational, and thermodynamical behaviors of new double antiperovskite (DAP) Cs 6 AgBiX 2 (X = Cl, Br, I) were studied. The band structure was calculated with and without spin orbit coupling (SOC). Using the TB-mBJ approach (Hybrid) revealed bandgap values of 1.504 eV, 1.491 eV, and 1.392 eV for Cs 6 AgBiCl 2 , Cs 6 AgBiBr 2 , and Cs 6 AgBiI 2 , respectively. Optical characteristics were studied to ascertain the light absorbing ability of Cs 6 AgBiX 2 . The elastic and vibrational (phonon) properties demonstrate that Cs 6 AgBiCl 2 and Cs 6 AgBiBr 2 are stable but Cs 6 AgBiI 2 is not. The calculated optimal bandgap and high absorption coefficient of Cs 6 AgBiCl 2 and Cs 6 AgBiBr 2 , suggest their potential for solar cell applications. Moreover, our photocatalytic results suggest that these materials have high oxidizing capacity that can be used to efficiently produce oxygen cheaply using solar water splitting., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)