Shifting in optoelectronic properties from pure K2O and Rb2O compounds to their V- and Cr-doped alloys

First principle calculations within the density functional theory (DFT) have been used in this approach to study the electronic and optical properties of vanadium (V) and chromium (Cr) doped K2O and Rb2O compounds. Based on the structure properties reported in our previous work, the study of electronic and optoelectronic properties of V- and Cr-doped K2O and Rb2O alloys have been vastly investigated. K2O and Rb2O are found to be semiconductors while their V- and Cr-alloys are metallic in nature. The optical functions like complex dielectric constant, complex index of refraction, absorption coefficient, and reflectivity of these alloys are computed and compared with those of pure K2O and Rb2O compounds. It has been shown that due to TM-doping (TM = V and Cr transition metals), many distinguished peaks appeared in the lower energy part (infrared) of the spectrum. The negative value of [Formula: see text] ([Formula: see text]) in this energy range confirmed the metallic behavior of these alloys. Furthermore, the frequency-dependent optical conductivity is also predicted in the entire spectrum, where it increases with increasing photon energy for all the studied alloys. The significant results of [Formula: see text] ([Formula: see text]) predict that all these compounds are useful in different optoelectronic applications in a wide part of the spectrum (between 13 eV and 27 eV).

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Elastic and optical properties of sillenites: First principle calculations

Ferroelectrics ◽

10.1080/00150193.2020.1713354 ◽

2020 ◽

Vol 557 (1) ◽

pp. 98-104 ◽

Cited By ~ 1

Author(s):

Husnu Koc ◽

Selami Palaz ◽

Sevket Simsek ◽

Amirullah M. Mamedov ◽

Ekmel Ozbay

Keyword(s):

Optical Properties ◽

Electronic Structures ◽

Density Functional ◽

Electronic Band Structure ◽

First Principle ◽

Electronic Band ◽

Functional Theory ◽

First Principle Calculations ◽

Optical Functions ◽

The Density Functional Theory

In the present paper, we have investigated the electronic structure of some sillenites - Bi12MO20 (M = Ti, Ge, and Si) compounds based on the density functional theory. The mechanical and optical properties of Bi12MO20 have also been computed. The second-order elastic constants have been calculated, and the other related quantities have also been estimated in the present work. The band gap trend in Bi12MO20 can be understood from the nature of their electronic structures. The obtained electronic band structure for all Bi12MO20 compounds is semiconductor in nature. Similar to other oxides, there is a pronounced hybridization of electronic states between M-site cations and anions in Bi12MO20. Based on the obtained electronic structures, we further calculate the frequency-dependent dielectric function and other optical functions.

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Size engineering optoelectronic features of C, Si and CSi hybrid diamond-shaped quantum dots

RSC Advances ◽

10.1039/c9ra04001c ◽

2019 ◽

Vol 9 (49) ◽

pp. 28609-28617 ◽

Cited By ~ 4

Author(s):

H. Ouarrad ◽

F.-Z. Ramadan ◽

L. B. Drissi

Keyword(s):

Density Functional Theory ◽

Quantum Dots ◽

Ab Initio ◽

Density Functional ◽

Optoelectronic Properties ◽

Many Body ◽

Functional Theory ◽

The Density Functional Theory

Based on the density functional theory and many-body ab initio calculations, we investigate the optoelectronic properties of diamond-shaped quantum dots based graphene, silicene and graphene–silicene hybrid.

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Electronic structures, elastic, magnetic properties and half-metallicity in PtONa3 anti-perovskite

Modern Physics Letters B ◽

10.1142/s0217984919503627 ◽

2019 ◽

Vol 33 (29) ◽

pp. 1950362 ◽

Cited By ~ 1

Author(s):

Oum Elkheir Youb ◽

Zoubir Aziz ◽

Feyza Zahira Meghoufel ◽

Bouadjemi Boubdellah ◽

Djoher Chenine ◽

...

Keyword(s):

Magnetic Properties ◽

Density Functional ◽

Full Potential ◽

Generalized Gradient ◽

Half Metallicity ◽

Metallic Behavior ◽

Functional Theory ◽

The Density Functional Theory ◽

Spin Polarized ◽

Linearized Augmented Plane Wave

The structural, elastic, electronic and magnetic properties of the cubic [Formula: see text] anti-perovskite are investigated by means of the full-potential linearized augmented plane wave (FP-LAPW) method based on the density functional theory (DFT). We have used three approximations: the generalized gradient (GGA), the GGA+[Formula: see text][Formula: see text], where [Formula: see text] is on-site Coulomb interaction correction, and the modified Becke–Johnson (mBJ-GGA). The elastic constants [Formula: see text] show that our compounds are ductile and anisotropic. The results obtained for the spin-polarized band structure and the density of states show a half-metallic behavior for the compounds using the GGA, GGA+[Formula: see text][Formula: see text] and mBJ-GGA approaches. These results make [Formula: see text] a promising candidate for spintronics applications.

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The surface effect on the thermodynamic stability, half-metallic and optical properties of Co2MnGa(001) films: a DFT study

International Nano Letters ◽

10.1007/s40089-019-00289-3 ◽

2019 ◽

Vol 9 (4) ◽

pp. 339-348

Author(s):

R. Ashtari Faregh ◽

A. Boochani ◽

S. R. Masharian ◽

F. H. Jafarpour

Keyword(s):

Density Functional Theory ◽

Thermodynamic Stability ◽

Density Functional ◽

Surface Effect ◽

Optical Parameters ◽

Metallic Behavior ◽

Functional Theory ◽

Half Metallic ◽

The Density Functional Theory ◽

Full Heusler

Abstract In this study, the half-metallic properties, thermodynamic stability and optical parameters of the full-Heusler Co2MnGa compound and its four different terminations of Co–Co, Co–Mn, Mn–Ga and Co–Ga from the surface of Co2MnGa (001) have been calculated based on the density functional theory (DFT). The results confirm the ferromagnetic half-metallic behavior with a magnetic moment of 4.08 $$ \mu_{\text{B}} $$μB and a gap of 0.32 eV at the Fermi level of Co2MnGa bulk phase having a Cu2MnAl-type structure. The density of states curves showed that all possible terminations from the Co2MnGa (001) surface eliminate the half-metallic behavior except the termination of Mn–Ga case. Moreover, the results indicate that the termination of Mn–Ga with the lowest surface energy is the most stable termination for the application in spintronics. The optical coefficients such as real and imaginary dielectric function, refraction, extinction, energy loss function, optical conductivity and reflections of the bulk and Mn–Ga termination have been calculated and compared.

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First Principles Study of Structural, Elastic, Electronic and Optical Features of the Non-centrosymmetric Superconductors SrMGe3 (Where M= Ir, Pt, and Pd)

International Journal of Material and Mathematical Sciences ◽

10.34104/ijmms.020.016028 ◽

2020 ◽

pp. 16-28 ◽

Cited By ~ 3

Keyword(s):

Fermi Level ◽

First Principles ◽

Density Functional ◽

Mechanical Stability ◽

Lattice Parameters ◽

Anisotropic Behavior ◽

Metallic Behavior ◽

Functional Theory ◽

The Density Functional Theory ◽

Atomic Populations

BaNiSn3-type superconductors SrIrGe3, SrPdGe3, and SrPtGe3 have a critical temperature of 1.80 K, 1.49K and 1.0K respectively have been reported recently. Employing the first-principles method based on the density functional theory, we have examined the physical properties including structural, elastic, electronic, and optical phenomena of all these structures. For all the phases our optimized lattice parameters are well accord to the experimental lattice parameters. The positive elastic constants of these compounds revealed that these superconductors possess mechanical stability in nature. The values of Pugh’s ratio and Poisson’s ratio ensured the brittle manner of these compounds and anisotropic behavior is ensured by the values of anisotropy factor. The soft nature of all compounds is confirmed by the bulk modulus analysis. The values of Vickers's hardness indicate that the rigidity decreased in the order of SrIrGe3>SrPtGe3>SrPdGe3. The overlapping of the conduction band and valence band at Fermi level indicates the zero band gaps and metallic nature of SrIrGe3, SrPdGe3, and SrPtGe3. The chief contribution around the Fermi level arises from Ir-5d, Ge-4s, 4p states for SrIrGe3 and Ge-4s, 4p states for SrPdGe3 and Pt-5d, Ge-4s, 4p for SrPtGe3 compound. The study of DOS, Mulliken atomic populations, and charge density ensured the existence of complex bonding in SrIrGe3, SrPdGe3, and SrPtGe3 with ionic, covalent, and metallic characteristics. The analysis of the dielectric function also ensured the metallic behavior of all these compounds.

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Absorption of Isopropanol on Surface of Defect Silicene

VNU Journal of Science Mathematics - Physics ◽

10.25073/2588-1124/vnumap.4525 ◽

2020 ◽

Vol 36 (3) ◽

Author(s):

Vo Van On ◽

Pham Trong Lam ◽

Dinh Van An

Keyword(s):

Charge Transfer ◽

Density Functional ◽

Lower Layer ◽

Density Functional Theory Method ◽

Metallic Behavior ◽

Functional Theory ◽

The Density Functional Theory ◽

Gap Characteristics ◽

Charge Analysis ◽

Bader Charge Analysis

In this work, we investigate the defect structure of Silicene with a vancacy and the adsorption mechanism of isopropanol on the surface of defected Silicene by employing the Density Functional Theory method. The adsorption profile was determined based on van der Waals functional optPBE-vdW and the charge transfer between isopropanol and silicene this system was also calculated by Bader charge analysis method. In the defected Silicene, Si vacancy preferably forms on the lower layer of the bulking structure. As a Si vacancy is introduced, Silicene exhibits a metallic behavior with zero bandgap. Due to the losing electron of defected Silicene, isopropanol is adsorbed on the surface with the most favourable adsorption configuration in which oxygen atom towards the surface of Silicene. Isopropanol adsorption opens a tunnelling gap of defected Silicence, resulting in the mili-gap characteristics of the adsorbed Silicene system. The adsorption profile of this volatile organic compound on defected Silicene implies the physics adsorption characteristics. The adsorption energy for isopropanol was found to be -0.40 eV. In addition, the charge transfer of 0.24 electron was obtained

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Synthesis and Physical Properties of Iridium-Based Sulfide Ca1−xIr4S6(S2) [x = 0.23–0.33]

Electronic Materials ◽

10.3390/electronicmat3010004 ◽

2022 ◽

Vol 3 (1) ◽

pp. 41-52

Author(s):

Michael Vogl ◽

Martin Valldor ◽

Roman Boy Piening ◽

Dmitri V. Efremov ◽

Bernd Büchner ◽

...

Keyword(s):

Density Functional ◽

Magnetic Measurements ◽

X Ray Diffraction ◽

Metallic Behavior ◽

Functional Theory ◽

X Ray ◽

Lattice Constants ◽

The Density Functional Theory ◽

Xrd Techniques

We present the synthesis and characterization of the iridium-based sulfide Ca1−xIr4S6(S2). Quality and phase analysis were conducted by means of energy-dispersive X-ray spectroscopy (EDXS) and powder X-ray diffraction (XRD) techniques. Structure analysis reveals a monoclinic symmetry with the space group C 1 2/m 1 (No. 12), with the lattice constants a = 15.030 (3) Å, b = 3.5747 (5) Å and c = 10.4572 (18) Å. Both X-ray diffraction and EDXS suggest an off-stoichiometry of calcium, leading to the empirical composition Ca1−xIr4.0S6(S2) [x = 0.23–0.33]. Transport measurements show metallic behavior of the compound in the whole range of measured temperatures. Magnetic measurements down to 1.8 K show no long range order, and Curie–Weiss analysis yields θCW = −31.4 K, suggesting that the compound undergoes a magnetic state with short range magnetic correlations. We supplement our study with calculations of the band structure in the framework of the density functional theory.

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First Principles Investigation of the Optoelectronic Properties of Molybdenum Dinitride for Optical Sensing Applications

Chemistry Proceedings ◽

10.3390/csac2021-10429 ◽

2021 ◽

Vol 5 (1) ◽

pp. 27

Author(s):

Amall A. Ramanathan

Keyword(s):

Density Functional ◽

Optical Constants ◽

Optical Sensing ◽

Optoelectronic Properties ◽

Full Potential ◽

Functional Theory ◽

Augmented Plane Wave ◽

Sensing Applications ◽

The Density Functional Theory ◽

Linearized Augmented Plane Wave

The electronic and optical properties of the newly synthesized molybdenum dinitride (MoN2) in the hypothetical 2H structure analogous to MoS2 is investigated using the density functional theory (DFT) full potential linearized augmented plane wave (FP-LAPW) method and the modified Becke–Johnson (mBJ) approximation. The aim is to investigate the optoelectronic properties of this compound for potential optical sensing applications and compare with the capabilities of MoS2 in this field. As compared to MoS2, which is a semiconductor, MoN2 is found to be a semi metal from the band structure plots. The dielectric function, optical conductivity and the optical constants, namely, the refractive index, the reflectivity, the extinction and absorption coefficients, are evaluated and compared with those of MoS2 and discussed with reference to the sensing performance.

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Первопринципное иследование полуметаллических свойств сплавов Гейслера Mn-=SUB=-2-=/SUB=-ScZ (Z=Al, Si, P, Ga, Ge, As, In, Sn, Sb)

Физика твердого тела ◽

10.21883/ftt.2021.11.51572.18s ◽

2021 ◽

Vol 63 (11) ◽

pp. 1751

Author(s):

Д.Р. Байгутлин ◽

В.В. Соколовский ◽

О.Н. Мирошкина ◽

В.Д. Бучельников

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Heusler Alloys ◽

Metallic State ◽

Metallic Behavior ◽

Functional Theory ◽

Half Metallic ◽

Spintronic Devices ◽

Exchange Correlation ◽

The Density Functional Theory

The properties of Heusler alloys of the Mn2ScZ family (Z = Al, Si, P, Ga, Ge, As, In, Sn, Sb) are investigated within the framework of the density functional theory. The PBE GGA and meta-GGA SCAN functionals were used for approximation of the exchange-correlation interactions. Calculations show that PBE does not predict ideal half-metallic behavior, unlike SCAN. It is shown that at Z = P, Si, a transition from the half-metallic state to the metallic one is observed. This effect can be used to develop tunable spintronic devices.

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