First-Principles Studies for Electronic Structure and Optical Properties of Strontium Doped β-Ga2O3

The crystal structure, electron charge density, band structure, density of states, and optical properties of pure and strontium (Sr)-doped β-Ga2O3 were studied using the first-principles calculation based on the density functional theory (DFT) within the generalized-gradient approximation (GGA) with the Perdew–Burke–Ernzerhof (PBE). The reason for choosing strontium as a dopant is due to its p-type doping behavior, which is expected to boost the material’s electrical and optical properties and maximize the devices’ efficiency. The structural parameter for pure β-Ga2O3 crystal structure is in the monoclinic space group (C2/m), which shows good agreement with the previous studies from experimental work. Bandgap energy from both pure and Sr-doped β-Ga2O3 is lower than the experimental bandgap value due to the limitation of DFT, which will ignore the calculation of exchange-correlation potential. To counterbalance the current incompatibilities, the better way to complete the theoretical calculations is to refine the theoretical predictions using the scissor operator’s working principle, according to literature published in the past and present. Therefore, the scissor operator was used to overcome the limitation of DFT. The density of states (DOS) shows the hybridization state of Ga 3d, O 2p, and Sr 5s orbital. The bonding population analysis exhibits the bonding characteristics for both pure and Sr-doped β-Ga2O3. The calculated optical properties for the absorption coefficient in Sr doping causes red-shift of the absorption spectrum, thus, strengthening visible light absorption. The reflectivity, refractive index, dielectric function, and loss function were obtained to understand further this novel work on Sr-doped β-Ga2O3 from the first-principles calculation.

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The structural, electronic and optical properties of Au–ZnO interface structure from the first-principles calculation

Modern Physics Letters B ◽

10.1142/s0217984918501075 ◽

2018 ◽

Vol 32 (07) ◽

pp. 1850107 ◽

Cited By ~ 2

Author(s):

Jin-Rong Huo ◽

Lu Li ◽

Hai-Xia Cheng ◽

Xiao-Xu Wang ◽

Guo-Hua Zhang ◽

...

Keyword(s):

Optical Properties ◽

Density Of States ◽

First Principles ◽

Density Functional ◽

Interface Structure ◽

First Principles Calculation ◽

Total Density ◽

Electronic Density ◽

Electronic And Optical Properties ◽

Interface Structures

The interface structure, electronic and optical properties of Au–ZnO are studied using the first-principles calculation based on density functional theory (DFT). Given the interfacial distance, bonding configurations and terminated surface, we built the optimal interface structure and calculated the electronic and optical properties of the interface. The total density of states, partial electronic density of states, electric charge density and atomic populations (Mulliken) are also displayed. The results show that the electrons converge at O atoms at the interface, leading to a stronger binding of interfaces and thereby affecting the optical properties of interface structures. In addition, we present the binding energies of different interface structures. When the interface structure of Au–ZnO gets changed, furthermore, varying optical properties are exhibited.

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Effects of Si Doping on the Structural, Electronic and Optical Properties of Barium Chalcogenide BaS: A First-Principles Study

SPIN ◽

10.1142/s2010324720500149 ◽

2020 ◽

Vol 10 (02) ◽

pp. 2050014

Author(s):

H. Absike ◽

H. Labrim ◽

B. Hartiti ◽

H. Ez-Zahraouy

Keyword(s):

Optical Properties ◽

First Principles ◽

Density Functional ◽

Original Structure ◽

Functional Theory ◽

Electron Charge Density ◽

Electronic And Optical Properties ◽

Charge Densities ◽

The Density Functional Theory ◽

Si Doped

In this work, the structural, electronic and optical properties of Si-doped barium chalcogenide [barium sulfide (BaS)] with different Si concentrations ([Formula: see text]) are investigated by the first-principles calculations based on the density functional theory (DFT). The band structures, charge densities and complex dielectric functions of the pure as well as Si-doped BaS were presented and analyzed in detail using TB-mBJ approach by WIEN2k package. It is found that silicon concentration can control the bandgap by reducing it to values around 1.4[Formula: see text]eV and 1.6[Formula: see text]eV for 12.5% and 6.25% of Si-doped BaS, respectively. The electron charge density indicates the ionic bonding between silicon and sulfur atoms due to the high electronegativity between them. In fact, the results show that the absorption peaks of Si-doped BaS are enhanced compared with pure BaS. These results suggest that the Ba[Formula: see text]SixS original structure displays excellent physical properties thereby revealing that it is a promising material in advanced optoelectronic and solar cell applications.

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Electronic structure and optical properties of CsI under high pressure: a first-principles study

RSC Advances ◽

10.1039/c7ra08777b ◽

2017 ◽

Vol 7 (83) ◽

pp. 52449-52455 ◽

Cited By ~ 6

Author(s):

Qiang Zhao ◽

Zheng Zhang ◽

Xiaoping Ouyang

Keyword(s):

Density Functional Theory ◽

High Pressure ◽

Optical Properties ◽

Electronic Structure ◽

First Principles ◽

Calculation Method ◽

Density Functional ◽

First Principles Calculation ◽

Functional Theory ◽

First Principles Study

We investigated the effects of high pressure on the electronic structure and optical properties of a CsI crystal through a first-principles calculation method based on density functional theory.

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Theoretical and experimental studies of Ba2SmTaO6 on crystal structure, electronic structure and optical properties

Journal of Materials Chemistry C ◽

10.1039/c7tc05171a ◽

2018 ◽

Vol 6 (7) ◽

pp. 1806-1814

Author(s):

Jiayi Zheng ◽

Song Wang ◽

Lihong Gao ◽

Zhuang Ma ◽

Fuchi Wang ◽

...

Keyword(s):

Crystal Structure ◽

Optical Properties ◽

Electronic Structure ◽

First Principles ◽

Experimental Studies ◽

Experimental Methods ◽

First Principles Calculation

The crystal structure, electronic structure and optical properties of Ba2SmTaO6 have been studied by first-principles calculation, including GGA and GGA+U, as well as by experimental methods.

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Electronic and optical properties of pentagonal-B2C monolayer: A first-principles calculation

International Journal of Modern Physics B ◽

10.1142/s0217979217500448 ◽

2017 ◽

Vol 31 (08) ◽

pp. 1750044 ◽

Cited By ~ 13

Author(s):

Mosayeb Naseri ◽

Jafar Jalilian ◽

A. H. Reshak

Keyword(s):

Optical Properties ◽

First Principles ◽

Density Functional ◽

Electronic Band Structure ◽

Valence Band Maximum ◽

First Principles Calculation ◽

Electronic Band ◽

Electronic And Optical Properties ◽

Energy Consideration ◽

Normal Light

The electronic and optical properties of pentagonal B2C (penta-B2C) monolayer are investigated by means of the first-principles calculations in the framework of the density functional theory. The cohesive energy consideration confirms the good stability of the B2C nanostructure in this phase. The electronic band structure reveals that the valence band maximum (VBM) is located at [Formula: see text]-point of the first Brillouin zone (BZ) whereas the conduction band minimum (CBM) is situated at the center of the BZ, resulting in an indirect energy bandgap of about 1.5 eV. Furthermore, a calculated low absorption and low reflection of the material in low energy ranges denote the transparency of the B2C monolayer in the investigated range for normal light incidence. The obtained results may find application in fabrication of future opto-electronic devices.

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First-principles study of electronic and optical properties of Sr2ZnN2 under pressure

Modern Physics Letters B ◽

10.1142/s0217984916501396 ◽

2016 ◽

Vol 30 (10) ◽

pp. 1650139

Author(s):

Kai Liang ◽

Hui Zhao

Keyword(s):

Refractive Index ◽

Optical Properties ◽

Electronic Structure ◽

Dielectric Function ◽

First Principles ◽

Density Functional ◽

Optical Transition ◽

Dft Method ◽

Structural Parameter ◽

Generalized Gradient

First-principles calculations of ternary Sr2ZnN2 compound using density-functional theory (DFT) method within the generalized gradient approximation (GGA) has been performed. Based on the optimized structural parameter, the electronic properties and optical properties have been researched. The calculated lattice constants are in agreement with the experimental and theoretical results. The electronic structure have been investigated throughout the calculated band structure and density of states (DOS). It shows that this compound belongs to the semiconductors with a band gap of about 0.775[Formula: see text]eV. Furthermore, in order to clarify the optical transition of this material, the optical properties such as dielectric function, absorption coefficient, reflectivity, refractive index and energy-loss function at different pressures of 0, 10 and 20[Formula: see text]GPa in the energy range 0–20[Formula: see text]eV were performed and discussed. It shows that Sr2ZnN2 is a strong anisotropy material and the imaginary part of dielectric function shifts to higher energy region as the pressure increases. The square of calculated static refractive index is equal to static dielectric function, which corresponds to the theory formula. In conclusion, pressure is a effective method to change the electronic structure and optical properties.

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First-Principles Calculations on Atomic and Electronic Properties of Ge/4H-SiC Heterojunction

Advances in Condensed Matter Physics ◽

10.1155/2018/8010351 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9

Author(s):

Bei Xu ◽

Changjun Zhu ◽

Xiaomin He ◽

Yuan Zang ◽

Shenghuang Lin ◽

...

Keyword(s):

Charge Density ◽

Electronic Properties ◽

Density Of States ◽

First Principles ◽

Density Functional ◽

First Principles Calculation ◽

Partial Density ◽

Total Charge ◽

Relaxation Energy ◽

Total Charge Density

First-principles calculation is employed to investigate atomic and electronic properties of Ge/SiC heterojunction with different Ge orientations. Based on the density functional theory, the work of adhesion, relaxation energy, density of states, and total charge density are calculated. It is shown that Ge(110)/4H-SiC(0001) heterointerface possesses higher adhesion energy than that of Ge(111)/4H-SiC(0001) interface, and hence Ge/4H-SiC(0001) heterojunction with Ge[110] crystalline orientation exhibits more stable characteristics. The relaxation energy of Ge(110)/4H-SiC(0001) heterojunction interface is lower than that of Ge(111)/4H-SiC(0001) interface, indicating that Ge(110)/4H-SiC(0001) interface is easier to form at relative low temperature. The interfacial bonding is analysed using partial density of states and total charge density distribution, and the results show that the bonding is contributed by the Ge-Si bonding.

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First-Principles Calculation of the Optical Properties of Nanocrystalline Silicon

MRS Proceedings ◽

10.1557/proc-358-3 ◽

1994 ◽

Vol 358 ◽

Cited By ~ 4

Author(s):

Masahiko Hirao

Keyword(s):

Optical Properties ◽

Crystallite Size ◽

First Principles ◽

Density Functional ◽

Energy Gap ◽

Nanocrystalline Silicon ◽

First Principles Calculation ◽

Nonradiative Recombination ◽

Dangling Bonds ◽

Hydrogen Atoms

ABSTRACTThe electronic structure and optical properties of nanocrystalline silicon were calculated by the first-principles density functional pseudopotential approach. The calculated energy-gap upshift from the bulk-Si value is nearly proportional to the reciprocal of the crystallite size. Dipole transitions across the gap are weakly allowed and the transition elements decrease rapidly with increases in the crystallite size. The apparent lifetime, the time over which the intensity decreases to 1/e of the initial value, decreases sharply from milliseconds to microseconds within a certain temperature range. The effect of dehydrogenation and the structural stability were investigated using an ab initio molecular dynamics technique. When some of the surface hydrogen atoms are removed, subsequent lattice relaxation eliminates dangling bonds. Further dehydrogenation creates mid-gap states due to surface dangling bonds, which act as nonradiative recombination centers. The calculated results are compared with observations of porous Si.

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Optical properties of Yb-doped LaB6 from first-principles calculation

Modern Physics Letters B ◽

10.1142/s0217984916500913 ◽

2016 ◽

Vol 30 (07) ◽

pp. 1650091 ◽

Cited By ~ 4

Author(s):

Luomeng Chao ◽

Lihong Bao ◽

Wei Wei ◽

O. Tegus

Keyword(s):

Optical Properties ◽

First Principles ◽

Density Functional ◽

Near Infrared ◽

Infrared Region ◽

Transmission Peak ◽

First Principles Calculation ◽

First Principles Calculations ◽

Plasmon Energy ◽

Functional Theory

The optical properties of Yb-doped LaB6 have been investigated by first-principles calculations within the framework of density functional theory. The results show that the Yb [Formula: see text] states at near Fermi surface affect their optical properties and the Yb-doping leads to a reduction of the plasmon energy of LaB6, i.e. a redshift of the position of transmission peak in the visible-near infrared region. This study offers a theoretical prediction for the design and application of Yb-doped LaB6 as an optoelectronic material.

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First-Principles Calculation of Optoelectronic Properties of Antimony Sulfides Thin Film

Physical Science International Journal ◽

10.9734/psij/2019/v22i130123 ◽

2019 ◽

pp. 1-10

Author(s):

A. B. Suleiman ◽

A. S. Gidado ◽

Abdullahi Lawal

Keyword(s):

Thin Film ◽

Thin Films ◽

Optical Properties ◽

Solar Cell ◽

First Principles ◽

Density Functional ◽

First Principles Calculation ◽

Full Potential ◽

Absorbing Layer ◽

Optical Behavior

Antimony sulfide (Sb2S3) thin film have received great interests as an absorbing layer for solar cell technology. Electronic and optical properties of Sb2S3 thin films were studied by first principles approach. Highly accurate full-potential linearized augmented plane wave (FP-LAPW) method within density functional theory (DFT) as implemented in WIEN2k package. The simulated film is in the [001] direction using supercell method with a vacuum along z-direction so that slab and periodic images can be treated independently. The calculated values of indirect band gaps of Sb2S3 for various slabs were found to be 0.568, 0.596 and 0.609 eV for 1, 2 and 4 slabs respectively. This trend is consistent with the experimental work where the band gap reduced when the thickness increased. Optical properties comprising of real and imaginary parts of complex dielectric function, absorption coefficient, refractive index was also investigated to understand the optical behavior of Sb2S3 thin films. From analysis of optical properties, it is clearly shown that Sb2S3 thin films have good optical absorption in the visible light and ultraviolet wavelengths, it is anticipated that these films can be used as an absorbing layer for solar cell and optoelectronic devices.

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