Recent advancements in thin-film growth techniques have opened doors for engineering innovative heterostructures with ultra-thin layers. These artificial superlattices hold promise for novel optoelectronic devices. However, a complete understanding of their properties is crucial for optimal design. In this study, we employ the full-potential linearized augmented plane wave (FP- LAPW) approach based on density functional theory (DFT) to engineer the optoelectronic properties of (HgSe) n /(ZnTe) n superlattices by controlling the number of layers (n) in SLs; The exchange-correlation potential was calculated by the generalized gradient GGA approximation and the optoelectronics properties has adjusted by the Tran-Blaha modified Becke-Johnson (TB- mBJ) correction of GGA approximation. Our findings shed light on the significant influence of stacking periodicity on the optoelectronic properties of HgTe/ZnTe SLs. We demonstrate that manipulating layer count is a viable strategy for engineering their optoelectronic characteristics. Additionally, the predicted near-infrared absorption makes these SLs promising candidates for near-infrared detector applications.

We performed first-principle calculations to investigate the structural, electronic, and magnetic properties of ZnS and ZnSe binary compounds, Zn0.5Cr0.5S and Zn0.5Cr0.5Se DMS alloys and (ZnS)2/Zn0.5Cr0.5Se and (ZnSe)2/Zn0.5Cr0.5S superlattices in the wurtzite structure using the full potential linear muffin–tin orbital (FP-LMTO) method. Features such as lattice constant, modulus of compressibility and its first derivative, spin-polarized band structures, total and local or partial electronic densities of states and magnetic properties were calculated. The electronic structure shows that Zn0.5Cr0.5S and Zn0.5Cr0.5Se DMS alloys and (ZnS)2/Zn0.5Cr0.5Se and (ZnSe)2/Zn0.5Cr0.5S superlattices are half-metallic ferromagnetic with 100% complete spin polarization. The total magnetic moments calculated show the same integer value of 4 µB, which confirms the ferromagnetic half-metallic behavior of these compounds. We found that the ferromagnetic state is stabilized by the p-d exchange associated with the double-exchange mechanism. Zn0.5Cr0.5S and Zn0.5Cr0.5Se DMS alloys and (ZnS)2/Zn0.5Cr0.5Se and (ZnSe)2/Zn0.5Cr0.5S superlattices are shown to be promising new candidates for applications in the fields of spintronics.

Herein, an ab initio study was conducted to investigate the properties of CoZrSb 1− x Bi x half-Heusler alloys and their (CoZrSb) n /(CoZrBi) n superlattices. The structural stability revealed that the α-phase minimized the total energy and was introduced as the ground-state structure for all studied materials. The chemical and dynamic stability of these materials was investigated. In addition, the elastic constants showed that the mechanical stability criteria were satisfied, confirming that materials were mechanically stable. From the electronic structures, the bandgap at the Fermi level confirmed the semiconductor behavior of all materials. The thermal transport properties were analyzed using Slack’s model and the BoltzTraP package. The obtained lattice and electronic thermal conductivity results suggest that these materials can be used as promising materials for thermoelectric devices owing to their low thermal conductivity.

The inspection of materials supporting topological excitations is one of the prospective areas of condensed matter physics. This paper is devoted to studying the possibility of the existence of topological phases in Na2CuX (X= As, Sb, Sn and Bi) full Heusler compounds using the FP-LMTO (Full-Potential Linear Muffin-Tin Orbital) method with and without spin-orbit coupling (SOC). The study of structural properties has found that these materials are energetically stable in the Hg2CuTi type structure. Also, formation energy calculations have shown that these materials are convenient to manufacture. Otherwise, band structure calculations show that these materials exhibit the behavior of non-trivial topological materials with a semi-metallic nature. The obtained results in this study, generally, showed that SOC is not a primary cause of the band inversion mechanism.

In the present study we discuss the effect of variation in the number of monolayers n on the electronic and optical properties of superlattices (SLs) (ZnSe)n/(ZnTe)n. The total energies were calculated by the full-potential linear muffin-tin orbital (FP-LMTO) method, and the exchange-correlation energy was applied in the local density approximation (LDA). First, the calculations show a decrease in the derivative of bulk modulus and electronic bandgap with an increase in the number of monolayers n. Second, the radiation energies up to 15 eV, the dielectric function ε(ω), the refractive index n(ω), and the reflectivity R(ω) are studied. These calculations may be beneficial to understand the properties of short-period superlattices (ZnSe)n/(ZnTe)n.

In this paper, we present the results of a detailed computational study of the structural, electronic, optical, magnetic and thermoelectric properties of the CsNiO\n $$_{\\mathrm {2}}$$\n and CsCuO\n $$_{\\mathrm {2}}$$\n Heusler alloys, by using the full potential-linearised augmented plane wave (FP-LAPW) method. The calculated structural parameters of the title compounds are in excellent agreement with the available theoretical data. The equilibrium ground-state properties were calculated and it was showed that the studied compounds are energetically stable in the AlCu\n $$_{\\mathrm {2}}$$\n Mn phase within the ferromagnetic state. In order to evaluate the stability of our compounds, the cohesion energies and formation energies have been evaluated. The optoelectronic and magnetic properties revealed that these compounds exhibit half-metallic ferromagnetic behaviour with large semiconductor and half-metallic gaps. This behaviour is confirmed by the integer values of total magnetic moments, but these compounds do not satisfy the Slater–Pauling rule. Furthermore, the thermoelectric parameters are computed in a large temperature range of 300–800 K to explore the potential of these compounds for high-performance technological applications.

In this paper, we present the results of a detailed computational study of the structural, electronic, optical, magnetic and thermoelectric properties of the CsNiO $$_{\mathrm {2}}$$ and CsCuO $$_{\mathrm {2}}$$ Heusler alloys, by using the full potential-linearised augmented plane wave (FP-LAPW) method. The calculated structural parameters of the title compounds are in excellent agreement with the available theoretical data. The equilibrium ground-state properties were calculated and it was showed that the studied compounds are energetically stable in the AlCu $$_{\mathrm {2}}$$ Mn phase within the ferromagnetic state. In order to evaluate the stability of our compounds, the cohesion energies and formation energies have been evaluated. The optoelectronic and magnetic properties revealed that these compounds exhibit half-metallic ferromagnetic behaviour with large semiconductor and half-metallic gaps. This behaviour is confirmed by the integer values of total magnetic moments, but these compounds do not satisfy the Slater–Pauling rule. Furthermore, the thermoelectric parameters are computed in a large temperature range of 300–800 K to explore the potential of these compounds for high-performance technological applications.

Topological nontrivial nature are the latest phases to be discovered in condensed matter physics with insulating bulk band gaps and topologically protectedmetallic surface states; they are one of the current hot topics because of their unique properties and potential applications. In this paper, we have highlighted a first-principles study of the structural stability and electronic behavior of the Na2AgX (X= As, Sb and Bi) full Heusler compounds, using the Full-Potential Linear Muffin-Tin Orbital (FP-LMTO) method. We have originated that the Hg2CuTi structure is appropriate in all studied materials. The negative values of the calculated formation energies mean that these compounds are energetically stable. The band structure is studied for the two cases relating the existence and the absence of spin-orbital couplings, where all materials are shown to be topologically non-trivial compounds. Spin orbital couplings were noticed to have no significant effect on the electronic properties such as the topological order.

In this paper, we present the results of a detailed computational study of the structural, electronic, optical, magnetic and thermoelectric properties of the CsNiO _2 and CsCuO _2 Heusler alloys, by using the full potential-linearised augmented plane wave (FP-LAPW) method. The calculated structural parameters of the title compounds are in excellent agreement with the available theoretical data. The equilibrium ground-state properties were calculated and it was showed that the studied compounds are energetically stable in the AlCu _2 Mn phase within the ferromagnetic state. In order to evaluate the stability of our compounds, the cohesion energies and formation energies have been evaluated. The optoelectronic and magnetic properties revealed that these compounds exhibit half-metallic ferromagnetic behaviour with large semiconductor and half-metallic gaps. This behaviour is confirmed by the integer values of total magnetic moments, but these compounds do not satisfy the Slater–Pauling rule. Furthermore, the thermoelectric parameters are computed in a large temperature range of 300–800 K to explore the potential of these compounds for high-performance technological applications.

The aim of this work was to study by means of the full potential linear muffin-tin orbital method within generalized gradient approximation (GGA) and GGA + U approach the various physical properties of the NbCoSn and NbFeSb half-Heusler compounds. The equilibrium ground states properties were calculated and compared with available experimental and theoretical data. The elastic constants have been calculated, and revealed that our compounds are mechanically stable. The obtained elastic modulus divulged that our compounds are elastically anisotropic and categorizing them as brittle compounds. The GGA approach showed a semi-conductor nature. However, the GGA + U approach showed a significant improvement over other theoretical work. We remarked from the band structures that the two materials showed a p-type semiconductor, with relatively high power factors. Furthermore, the optical quantities are calculated and discussed in detail. Hence, by our findings, the studied compounds could be used for thermoelectric and optoelectronic applications.

In this paper, we studied the structural, electronic, magnetic, and optical properties of (ZnTe)m/(MnTe)n superlattices with very small size layers (m-n: 1-1, 2-2, and 3-1). This work is purely theoretical and it's performed using the functional density theory (DFT) with the full-potential linear muffin-tin orbital (FP-LMTO) method implemented in the LmtART calculation code. We adopted the GGA + U formalism for the exchange-correlation potential. The obtained results demonstrate the existence of a strong correlation between the electronic, magnetic and optical properties of (ZnTe)m/(MnTe)n superlattices and their structural properties. In addition, and for more details on the behavior of these nanostructure systems, the density of states (DOS and PDOS), the s-d exchange constant (N-0 alpha) and the p-d exchange constant (N0(beta)) are calculated and analyzed. The dielectric function epsilon(omega) is calculated for radiation energies up to 35 eV. The obtained results show that the static dielectric constant increases significantly with the increase in the number of monolayers m.

In this paper, we have highlighted a first-principles study of the structural stability and electronic behavior of the novel alkali metal–based quaternary Heusler compounds (LiNaCuAs, LiKCuAs, NaKCuAs, LiRbCuAs, NaRbCuAs, and KRbCuAs), using the full-potential linear muffin-tin orbital (FP-LMTO) method. The obtained results show that our compounds are energetically more stable in the Hg2CuTi-type structure. The calculated electronic properties with and without spin-orbit coupling (SOC) effects indicate that the majority of compounds naturally present a band inversion order which confirmed the topological nontrivial behavior of these materials. In addition, our results show that SOC is not a primary cause of the band inversion mechanism. The obtained values of the calculated formation energy confirm the physical stability of these compounds against decomposition, and they can be passed in fabrication level.

In this study, we carried out ab-initio calculations of structural, electronic, optical and thermo-electric properties of CaTaO2N compound in Pnma orthorhombic structure, using the full-potential linearized augmented plane wave method (FP-LAPW), within the framework of density functional theory (DFT). The calculated structural parameters are found to be in good agreement with the experimental results. Moreover, we have studied the electronic band structure, total and partial density of states in order to explain the origin of band gaps and the nitrogen anion contribution in the valence and the conduction bands. The CaTaO2N band structure has shown a direct band gap in the direction [Formula: see text] (with the value 2.32[Formula: see text]eV). The optical properties represented by the dielectric functions for CaTaO2N compound have revealed that the Pnma structure absorbs the light at a large window in the edge UV-Vis regions. In order to explain the thermo-electric properties, we have calculated Seebeck coefficient, electrical conductivity, thermal conductivity and the factor figure of merit in this temperature range 100–1000 K. The factor figure of mérit (ZT) of CaTaO2N takes a maximum value of 0.775 at [Formula: see text][Formula: see text]K.

In this paper, we have conducted a theoretical works on the structural, electronic, mechanical and optical properties of inorganic lead bromide perovskite APbBr3 for comparison. The calculations have performed using the full potential linearized augmented plane waves (FP-LAPW) method within GGA-PBE formalism in ordered to describe the exchange-correlation potential. The obtained results showed that the equilibrium parameter values are in good agreement with the available results. For the mechanical properties, the obtained values reveal that all APbBr3 compounds are mechanically and dynamically stable. For electronic properties, the band structures analysis indicate that all compounds process semiconductor behavior. The optical constants indicated that all compounds are promising semiconductors for optoelectronic applications and above all as good candidates for photovoltaic applications. For all properties, the obtained results are stayed in good agreement with experimental ones, and they are very close to theoretical values.

We have conducted a first-principles study on the structural, electronic, optical and elastic properties of BeSiP(2 )and BeGeP2 chalcopyrite compounds. Using the density functional theory (DFT), implemented in both full potential linear muffin-fin orbital (FP-LMTO) and Vienna Ab initio simulation (VASP) packages. The FP-LMTO is used for the determination of the structural, electronic and optical properties, while the VASP is used to determine the elastic constants that give indications about the material stability. The obtained equilibrium structural parameters are in good agreement with available results. An investigation of the band gap indicates that our compounds possess a semiconductor behavior with direct band gap for BeSiP2 and with an indirect band gap for BeGeP2. The energy band gaps decreased by changing Be atoms from Si to Ge. We have calculated the dielectric function epsilon(omega). The obtained results show that these materials are promising semiconductors for photovoltaic applications. For the elastic properties, the single-crystal elastic constants C-ij, shear anisotropic factors A, as well as polycrystalline bulk, shear and Young's modulus (B, G and E) and Poisson's ratio v have been predicted. The generalized elastic stability criteria for a tetragonal crystal are well satisfied, indicating that BeSiP2 and BeGeP2 are mechanically stable in the chalcopyrite structure.

This work presents ab initio study of the structural, electronic, magnetic and mechanical properties of Fe 2 NiAl[Formula: see text]Ga x Heusler compounds with variable concentrations ([Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text]) of Ga. Calculations have performed using the full-potential linearized augmented plane waves (FP-LAPW) method within generalized gradient approximation Perdew–Burke–Ernzerhof (GGA-PBE) formalism in order to describe the exchange–correlation potential. The obtained results showed that the equilibrium parameter values are in good agreement with the available experimental results. In the study of the electronic properties, band structure analysis indicated that all of our compounds have metallic behavior. The calculated total magnetic moments of our Heusler alloys are in line with the Slater–Pauling rule, and they agreed with the results of previous studies. For mechanical properties, shear modulus, Young’s modulus, elastic constants, Poisson’s ratio and shear anisotropy factor have studied. Their obtained values reveal that these compounds are mechanically and dynamically stable.