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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]

Based on the first-principles calculations, we investigate the structural, electronic, and magnetic properties of defects in monolayer SnS. We study the formation and migration of vacancies at both Sn- and S-sites. In comparison to the S-site vacancy, our calculations show that creating a vacancy at the Sn-site requires lesser energy, indicating that the vacancy at the Sn-site is more likely to be formed in experiments with energetic particle irradiation. For the Sn-rich (S-rich) environment, the vacancy at the S-site (Sn-site) is more likely to be found than the vacancy at the Sn-site (S-site). Reducing the formation of vacancy clusters, the S vacancy remains at the position where it is created because of the high vacancy migration barrier. Both types of vacancies remain nonmagnetic. To induce magnetism in monolayer SnS, we also study the transition metal (TM = Mn, Fe, and Co) doping at the Sn-site and find a significant influence on the electronic and magnetic properties of monolayer SnS. The doping of TM changes non-magnetic monolayer SnS to magnetic one and keeps it semiconducting. Additionally, long-range ferromagnetic behavior is observed for all the doped system. Hence, doping TM atoms in monolayer SnS could be promising to realize a two-dimensional diluted magnetic semiconductor. More interestingly, all the doped TM configurations show a high spin state, which can be used in nanoscale spintronic applications such as spin-filtering devices. [ABSTRACT FROM AUTHOR]

This work reports experimental and computational magnetic phase transition from superconducting-diamagnet to ferromagnet in lanthanum (La)-doped functionalized Nb2C MXene. Co-precipitation method is used to synthesize La-doped Nb2C MXene. Structure and morphology of the compound are studied through x-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and energy dispersion spectroscopy, confirming the successful doping of La while retaining the two-dimensional (2D) structure of MXene. The magnetic properties of doped sample are studied using field-cooled and zero-field-cooled curves as well as from magnetization (M) versus applied magnetic field (H) graphs. Contrary to the superconductivity-like diamagnetic behavior in pristine Nb2C MXene, the La-doped MXene converts the diamagnetism into the ferromagnetic (FM) phases at all temperatures. The ferromagnetism arises due to the pinning of magnetic spins pinned by Lanthanum itself. The computational analysis of pristine Nb2C MXene confirms its diamagnetic behavior and further clarifies the role of La and functional groups (O and F) in the reduction of diamagnetic behavior in La-doped Nb2C MXene while inducing FM nature. This work provides an interesting superconducting-diamagnetic to FM transition with a possibility of its implementation in 2D spintronics. [ABSTRACT FROM AUTHOR]

We have performed first‐principles calculations to investigate the formation and migration of vacancies and doping with M (M = Ti, V, Co, Mo, W, Re) at the Sn sites and X (X = O, Se, Te) at the S sites in monolayer SnS2. We find that the formation energies for S vacancy under both Sn‐ and S‐rich environments are lower than those for Sn vacancy, indicating that the vacancies at the S sites are likely to be formed during the synthesis. Reducing the possibility of vacancy cluster formation, both the vacancies at the Sn and S sites remain robust due to high migration barrier. Additionally, SnS2 with the vacancies at the Sn sites induces magnetic ground states with a magnetic moment of 4.00 μB. Both the Sn‐ and S‐sites vacancies preserve the semiconducting nature of pristine SnS2 with band gaps of 2.47 eV and 0.30 eV, respectively. Furthermore, we find that the dopants Ti, V, Mo, W, Re can be easily incorporated at the Sn sites in monolayer SnS2 due to the low formation energies under the S‐rich environment. However, Co may not be easily incorporated into SnS2. The doping with M at the Sn sites induces magnetic ground states in non‐magnetic SnS2. Additionally, a long‐range magnetic ordering is observed in SnS2 doped with V, Co, and Mo. In contrast, easy incorporation of O, Se, and Te at the S sites under the Sn‐rich environment has been observed while the semiconducting nature of SnS2 preserves with small band gaps. [ABSTRACT FROM AUTHOR]

We have performed first‐principles calculations to investigate the formation and migration of vacancies and doping with M (M = Ti, V, Co, Mo, W, Re) at the Sn sites and X (X = O, Se, Te) at the S sites in monolayer SnS2. We find that the formation energies for S vacancy under both Sn‐ and S‐rich environments are lower than those for Sn vacancy, indicating that the vacancies at the S sites are likely to be formed during the synthesis. Reducing the possibility of vacancy cluster formation, both the vacancies at the Sn and S sites remain robust due to high migration barrier. Additionally, SnS2 with the vacancies at the Sn sites induces magnetic ground states with a magnetic moment of 4.00 μB. Both the Sn‐ and S‐sites vacancies preserve the semiconducting nature of pristine SnS2 with band gaps of 2.47 eV and 0.30 eV, respectively. Furthermore, we find that the dopants Ti, V, Mo, W, Re can be easily incorporated at the Sn sites in monolayer SnS2 due to the low formation energies under the S‐rich environment. However, Co may not be easily incorporated into SnS2. The doping with M at the Sn sites induces magnetic ground states in non‐magnetic SnS2. Additionally, a long‐range magnetic ordering is observed in SnS2 doped with V, Co, and Mo. In contrast, easy incorporation of O, Se, and Te at the S sites under the Sn‐rich environment has been observed while the semiconducting nature of SnS2 preserves with small band gaps. [ABSTRACT FROM AUTHOR]

Based on the first-principles calculations, we examine the effects of In/Sb/P doping on the structure, electronics, and magnetic properties of monolayer SnS. We have examined that the In-/Sb-/P-doped SnS is energetically more favorable under the S-rich condition due to high formation energies. The doping of In at Sn site keeps the semiconducting nature of monolayer SnS, and the Sb doping turns it to metallic. Interestingly, the In-doping turns the non-magnetic monolayer SnS to the magnetic one with a magnetic moment of 1.00 μ B. Additionally, the ferromagnetic behavior is observed at a larger distance confirming the large range ferromagnetism in the In-doped SnS. Importantly, for the In-doped system, a high MAE of 40.91 meV is calculated. Furthermore, the doping P at the S-site in monolayer SnS trun the semiconductor nature to a metallic one. Additional experimental studies into the efficient utilization of these systems in the fields of photo-electronics and magnetic semiconductor devices are very desirable. [ABSTRACT FROM AUTHOR]

This research explores the structural, electronic, magnetic, and optical properties of GaN-X (X = Sr, Ba, Cs, Mg) materials. First principle calculations based on full potential linearized augmented plane wave (FP-LAPW) method is executed in Wien2k code. PBE-GGA approximation is used to approximate exchange-correlation functional. Sr 3 d -states, Ba 5 p -states, Cs 5 p -states, and Mg 2 p -states help in improving electronic properties. The magnetic character of the proposed materials is revealed with net magnetic moment values of, 2.9639 μ B , 2.3316 μ B , 3.4179 μ B , and 3.1697 μ B , respectively. Optical absorption shows blueshift for Ba@GaN and Mg@GaN while Sr@GaN and Cs@GaN spectra show redshift. Absorption and conductivity are enhanced in the UV region, along with decrease in reflectivity. Optical response of proposed materials illustrate to make use of these materials for production of high energy UV optoelectronics, photonics, memory, spintronics and photovoltaic devices. [ABSTRACT FROM AUTHOR]

Current research is based on density functional theory investigations of structural, electronic, magnetic, and optical properties of X (X = Sm, La, Ce) doped CdS using Wien2k code. Spin-polarized calculations indicate non-magnetic character of pure and La doped CdS while magnetism is noticed upon Sm and Ce doping into CdS. Hubbard correction indicate shift of f -states toward the Fermi level and non-negative frequency modes in phonon spectra illustrate dynamical stability of proposed materials for synthesis. However, magnetic moment in Ce doped CdS (2.9188 μ B) is larger than Sm doped CdS (2.7901 μ B). Cd 4 d -states, S 3 p -states, La 5 d -, Sm and Ce 4 f -states show supreme role around the Fermi level which improve electronic properties. Reduction in band gap is noted which points good conduction. Optical absorption spectrum of impurities added CdS materials exhibit blueshift. Moreover, enhanced absorption and upgraded conductivity along with increasing refractive index of selected materials emphasize their potential uses in high energy UV photonics, sensors, spintronics, optoelectronics and energy harvesting devices. • Electronic, structural, magnetic, optical properties, phonon dispersion and band gap of Sm/La/Ce doped CdS were calculated using Wien2k. • Electronic properties have been studied with and without Hubbard correction. • Phonon spectra exhibited positive frequency modes. • Band gap was reduced with impurities addition into CdS. • Absorption spectra of proposed materials have shown blueshift in comparison to pure CdS. • Enhanced absorption and conductivity in the UV and visible region have illustrated potential uses of proposed materials in optoelectronics, photonics, and spintronics applications. [ABSTRACT FROM AUTHOR]

We investigate electronic, optical and magnetic properties of Al and Ga doped CeO 2 using first principle calculations. In order to approximate exchange and correlation potential, Perdew-Burke-Ernzerhof (PBE) based generalized gradient approximation is used in Wien2k code. Spin-polarized calculations manifest non-magnetic nature of CeO 2 while Al and Ga doped CeO 2 points magnetic character with net magnetic moment of 3.09 μ B and 2.03 μ B , respectively. p - d hybridization with enormous influence of Ce 4 f -, Al 3 p - and Ga 3 d -states is noted which tune electronic properties of selected materials. Optical absorption spectrum of pure CeO 2 shows blueshift upon incorporation of impurities. Upon addition of impurities, significant reduction in band gap of CeO 2 is noted. Improved absorption and conductivity along with decrease in reflectivity in the UV region embellish uses of these materials in the field of optoelectronics, photonics, solar, photocatalysis and spintronics. [Display omitted] • Electronic, magnetic, and optical properties of Al:CeO 2 and Ga:CeO 2 were performed using Wien2k. • Electronic properties were modified with Ce 4 f -, Al 3 p - and Ga 3 d -states along with p - d hybridization. • Al and Ga doping brings magnetism into CeO 2 with magnetic moment of 3.0518 μ B and 2.0422 μ B , respectively. • Adding impurities (Al, Ga) into CeO 2 have caused blueshift in absorption spectrum. • Blueshift and magnetism of Al:CeO 2 and Ga:CeO 2 points their potential applications in current optoelectronics, photovoltaics, photonics, and spintronics. [ABSTRACT FROM AUTHOR]

For leading spintronic technology, the significance of rare earth in the spinels chalcogenide MgCe 2 Z 4 (Z = S, Se) has been investigated. Wein2K and BoltzTraP program packages are used to calculate the magnetic and transport characteristics of the spinels. While comparing the energies within the ferromagnetic and nonmagnetic states, the ferromagnetic state stability in the ground state is examined. The formation energy, phonon dispersion curve, and mechanical stability conditions help clarify the issue of stability in the cubic ferromagnetic phase. Poisson's and Pugh's ratios are employed to ensure the brittle characteristics. To explore the electronic properties, modified Becke and Johnson (mBJ) potential are utilized to investigate both spinels' direct narrow bandgap (spin up channel) nature. Chalcogenide's 2p produces the total magnetic moments- and rare-earth metals' f-states, which result in significant hybridization around the Fermi level. The computed total magnetic moment integer values and polarization are used to demonstrate spin polarisation. Finally, the Seebeck coefficient, thermal-to-electrical conductivity ratio, and power factor are used to evaluate thermoelectric properties. [ABSTRACT FROM AUTHOR]

This research presents detailed investigations of the structural, electronic, magnetic and optical properties of cesium doped and Cs-X (X = Mn, Fe) co-doped CdS. We employ Perdew-Burke-Ernzerhof (PBE) generalized gradient approximation within Wien2K code. Cs-X (X = Mn, Fe) co-doped CdS materials exhibit magnetic moment and thus, show magnetic character. Role of 5 p -states of Cs atom and 3 d -states of Mn, Fe atoms appreciably tune the electronic properties. Optical absorption spectrum of Cs@CdS shows blueshift while Cs–Mn/Fe co-doping into CdS causes redshift. However, the ability of proposed materials to absorb electromagnetic radiations in the 0–7 eV energy range and presence of the magnetism illustrates their potential uses for fabrication of novel optoelectronic and spintronic devices. [Display omitted] • Structural, electronic, magnetic, and optical properties of pure CdS, Cs@CdS and Cs–Mn/Fe@CdS were calculated using DFT. • Cs doped CdS is non-magnetic while Cs–Mn/Fe caused magnetism into CdS. • Blueshift in absorption spectrum of Cs@CdS enable its uses in UV optoelectronics while absorption of Cs–Mn/Fe@CdS was red shifted. • Phonon dispersion illustrates absence of negative frequency, indicating materials stability. • Ability of materials to absorb electromagnetic radiations and magnetism indicate their uses for uses in novel optoelectronic and spintronic devices. [ABSTRACT FROM AUTHOR]

In current research, we study the effect of Os and Os-Mn/Ru co-doping onto the GaN. We study the electronic structure, optical, and magnetic properties of these materials. We employ the PBE-GGA approximation in the Wien2k code using density functional theory. The study of electronic properties reveals that Mn 3 d -states, Ru 4 d -states and Os 5 d -states highly influence the transfer of electrons from valence to conduction band. The Os-Mn/Ru co-doping turns GaN magnetic while Os doping does not alter non-magnetic character of GaN. Optical absorption spectra shows blueshift upon adding impurities and materials shows good absorption in the UV region. A decrease in reflectivity and increase in conductivity in the high energy UV region reveals that these materials may be used for fabrication of devices in the field of photonic, optoelectronic, photovoltaics, solar cells, photodetectors, and power electronics. [ABSTRACT FROM AUTHOR]

First-principles calculations have been carried out to investigate the optoelectronic and magnetic of Ga 1-x V x N (x ​= ​0, 0.027, 0.0625 and 0.125). Our results demonstrate that V(III) doping at Ga site not only affect the magnetic state of the GaN, but also significantly modify the electronic structure by generating impurity-derived states. The ferromagnetic coupling between V(III) ions is due to super-exchange mechanism. The super-exchange ferromagnetic mechanism is confirmed from the analysis of electronic structure and the arrangement of V(III) ions in the lattice of GaN crystal. We have estimated the Curie temperature (Tc) for different concentrations (5.5%, 12.5% and 25%) of V(III) ions within the mean field approximation and found that Tc can be expected above room temperature at higher concentration (>12%) of V(III) ions. The optical properties have been investigated using optical absorption spectra and we found that the V(III) doping increases the fundamental bandgap of GaN. The observed spin allowed d-d transition (3A 2 to 3T 2 transition) bands of V(III) ions take place in the visible region of the absorption spectrum and shows a red-shift with increasing V(III) content. Furthermore, the correlation of magnetic interaction with d-d transition of V(III) ions and bandgap of GaN is also discussed and we found that d-d transition bands show a red/blue shift for FM/AFM coupled V(III) ions. It is also observed that the fundamental bandgap of GaN in AFM is higher than that in FM configuration. [Display omitted] •The V(III) ions in the lattice of GaN interact ferromagnetically under the super-exchange ferromagnetic mechanism. •In the absorption spectrum of V(III)-doped GaN, the spin allowed d-d transition bands in V(III) ion appear in visible regions. •The intensity of d-d transition bands increases with the increase of V concentrations. •The d-d transition bands of V(III) ions show a red/blue shift for FM/AFM coupled V(III) ions. •The FM/AFM coupled V ions system narrow/enlarge the fundamental bandgap of GaN. [ABSTRACT FROM AUTHOR]

In the current research, we perform a density functional theory study of C, Ti mono- doped (C-@GaN, Ti@GaN), and their co-doped GaN (C-Ti@GaN). We investigate the effect of C, Ti and their co-doping on the structural, electronic, magnetic, and optical properties using the Wien2K code. The formation energy of mono- and co-doped GaN is negative under the N-rich conditions and co-doped material is more stable than the mono-doped material. Optical absorption of mono-doped GaN is redshifted while the absorption of co-doped material is blue shifted. Our calculated results are in accordance with the already reported literature. Since, we did not find magnetism in the C-Ti@GaN material and because of blueshift in absorption spectrum; we suggest that co-doped GaN is more favorable for the UV optoelectronics, power electronics, and the UV solar cells applications than the co-doped materials. [ABSTRACT FROM AUTHOR]

In this work, we use the density functional theory calculations to explore the effect of vanadium doping on optoelectronic and magnetic properties of wurtzite ZnS. The calculation results reveal that V-doped ZnS favors spin-polarized state with the total magnetization of 3.0 μ B per supercell. The ferromagnetic interaction between V spins in the lattice of ZnS is due to double exchange mechanism. Moreover, optical absorptions of undoped and doped systems were discussed and we found that the intensity of the main absorption peak of undoped ZnS becomes weak on V substitution. The spin-allowed d-d absorption peaks of V ions were observed in the near Infra-red light (NIR) and Visible light regions (VIs). The intensity of the intraband d-d absorption increases as the doping concentration increases. The correlation between the fundamental bandgap and the magnetic coupling between V spins shows that the AFM and FM coupled ions increases and decreases the fundamental bandgap, respectively. The results of optical and magnetic properties are interesting from a theoretical point of view and may open opportunities for V; ZnS in optoelectronic and spintronic devices. [ABSTRACT FROM AUTHOR]