Direct band gap nature and optical response of BexMgyZn1−(x+y)Se

For the first time, the electronic and optical properties of the quaternary Be[Formula: see text]Mg[Formula: see text]Zn[Formula: see text]Se alloy have been investigated using first-principles calculations within the framework of density functional theory (DFT). Variations in the direct band gap with the change in [Formula: see text] and [Formula: see text] compositions show agreement with the experimental measurements. Evaluation of the dielectric function and refractive index reveals the optical activity in the visible and ultraviolet energy regions.

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Indirect-Direct Band Gap Transition by Van Der Waals Interaction Engineering in MoS2/WS2 Bilayer Heterojunction

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.614.70 ◽

2014 ◽

Vol 614 ◽

pp. 70-74 ◽

Cited By ~ 2

Author(s):

Hai Ning Cao ◽

Zhi Ya Zhang ◽

Ming Su Si ◽

Feng Zhang ◽

Yu Hua Wang

Keyword(s):

Band Gap ◽

First Principles ◽

Electronic Structures ◽

Density Functional ◽

First Principles Calculations ◽

Functional Theory ◽

Direct Band Gap ◽

The Density Functional Theory ◽

Direct Band ◽

Electric Filed

First principles calculations based on the density functional theory (DFT) are employed to estimate the electronic structures of bilayer heterostructure of MoS2/WS2. The dependences of the band structures on external electric field and interlayer separation are evaluated. The external electric filed induces a semiconductor-metal transition. At the same time, a larger interlayer separation, corresponding to a weaker interlayer interaction, makes an indirect-direct band gap transition happen for the heterojunction. Our results demonstrate that electronic structure tailoring of two-dimensional layered materials should include both spatial symmetry control and interlayer vdW interactions engineering.

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First-Principles Investigations of Electronic, Dynamic and Thermodynamic Properties of α-MnO2

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.936.591 ◽

2014 ◽

Vol 936 ◽

pp. 591-595 ◽

Cited By ~ 3

Author(s):

Ai Min Hao ◽

Na Qi Wang

Keyword(s):

Thermodynamic Properties ◽

First Principles ◽

Electronic Structures ◽

Density Functional ◽

Dynamic Properties ◽

Thermodynamic Quantities ◽

First Principles Calculations ◽

Functional Theory ◽

Direct Band Gap ◽

Direct Band

We investigate the electronic, dynamic and thermodynamic properties of α-MnO2 using first-principles calculations based on density functional theory (DFT) with the GGA+U method. The results of electronic structures show that α-MnO2is a semiconductor with a direct band gap of 1.4 eV at Γ point. The results of dynamic properties indicate that the structure of α-MnO2 is dynamically unstable at ground-state. Several important thermodynamic quantities, such as entropy, enthalpy and Gibbs free energy, et al each as a function of temperature were presented.

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Strain-induced semimetal-to-semiconductor transition and indirect-to-direct band gap transition in monolayer 1T-TiS2

RSC Advances ◽

10.1039/c5ra16877e ◽

2015 ◽

Vol 5 (102) ◽

pp. 83876-83879 ◽

Cited By ~ 23

Author(s):

Chengyong Xu ◽

Paul A. Brown ◽

Kevin L. Shuford

Keyword(s):

Band Gap ◽

Electronic Properties ◽

Plane Strain ◽

Material Properties ◽

First Principles ◽

Tensile Strain ◽

First Principles Calculations ◽

Direct Band Gap ◽

Direct Band ◽

Uniform Plane

We have investigated the effect of uniform plane strain on the electronic properties of monolayer 1T-TiS2using first-principles calculations. With the appropriate tensile strain, the material properties can be transformed from a semimetal to a direct band gap semiconductor.

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First principles calculations on theoretical band gap improvement of IIIA-VA zinc-blende semiconductor InAs

International Journal of Modern Physics C ◽

10.1142/s0129183120501788 ◽

2020 ◽

Vol 31 (12) ◽

pp. 2050178

Author(s):

Waqas Mahmood ◽

Arfan Bukhtiar ◽

Muhammad Haroon ◽

Bing Dong

Keyword(s):

Band Gap ◽

Density Functional ◽

Local Density ◽

Lattice Parameter ◽

First Principles Calculations ◽

Functional Theory ◽

Zinc Blende ◽

Valence States ◽

Direct Band ◽

Experimental Findings

The structural, electronic, dielectric and vibrational properties of zinc-blende (ZB) InAs were studied within the framework of density functional theory (DFT) by employing local density approximation and norm-conserving pseudopotentials. The optimal lattice parameter, direct band gap, static dielectric constant, phonon frequencies and Born effective charges calculated by treating In-4d electrons as valence states are in satisfactory agreement with other reported theoretical and experimental findings. The calculated band gap is reasonably accurate and improved in comparison to other findings. This work will be useful for more computational studies related to semiconductor devices.

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Remarkable improvement in phosgene detection with a defect-engineered phosphorene sensor: first-principles calculations

Physical Chemistry Chemical Physics ◽

10.1039/d0cp00427h ◽

2020 ◽

Vol 22 (17) ◽

pp. 9677-9684 ◽

Cited By ~ 6

Author(s):

Mehdi Ghambarian ◽

Zahra Azizi ◽

Mohammad Ghashghaee

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Defect Engineering ◽

Functional Theory ◽

Remarkable Improvement ◽

Black Phosphorene ◽

First Time ◽

Theory Framework

A drastic improvement in the phosgene sensitivity of black phosphorene with defect engineering is reported for the first time within a periodic density functional theory framework.

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First principles study of silicene symmetrically and asymmetrically functionalized with halogen atoms

RSC Advances ◽

10.1039/c6ra18179a ◽

2016 ◽

Vol 6 (98) ◽

pp. 95846-95854 ◽

Cited By ~ 25

Author(s):

Wencheng Tang ◽

Minglei Sun ◽

Qingqiang Ren ◽

Yajun Zhang ◽

Sake Wang ◽

...

Keyword(s):

Band Gap ◽

First Principles ◽

Tensile Strain ◽

First Principles Calculations ◽

Direct Band Gap ◽

Halogen Atoms ◽

First Principles Study ◽

Direct Band

Using first principles calculations, we predicted that a direct-band-gap between 0.98 and 2.13 eV can be obtained in silicene by symmetrically and asymmetrically (Janus) functionalisation with halogen atoms and applying elastic tensile strain.

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The indirect to direct band gap transition in multilayered MoS2 as predicted by screened hybrid density functional theory

Applied Physics Letters ◽

10.1063/1.3672219 ◽

2011 ◽

Vol 99 (26) ◽

pp. 261908 ◽

Cited By ~ 337

Author(s):

Jason K. Ellis ◽

Melissa J. Lucero ◽

Gustavo E. Scuseria

Keyword(s):

Density Functional Theory ◽

Band Gap ◽

Density Functional ◽

Hybrid Density Functional Theory ◽

Functional Theory ◽

Direct Band Gap ◽

Direct Band ◽

Hybrid Density Functional

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Penta-MX2 (M = Ni, Pd and Pt; X = P and As) monolayers: direct band-gap semiconductors with high carrier mobility

Journal of Materials Chemistry C ◽

10.1039/c8tc06030d ◽

2019 ◽

Vol 7 (12) ◽

pp. 3569-3575 ◽

Cited By ~ 13

Author(s):

Shifeng Qian ◽

Xiaowei Sheng ◽

Xian Xu ◽

Yuxiang Wu ◽

Ning Lu ◽

...

Keyword(s):

Band Gap ◽

First Principles ◽

Carrier Mobility ◽

Two Dimensional ◽

First Principles Calculations ◽

Ring Network ◽

Direct Band Gap ◽

Direct Band ◽

High Carrier Mobility ◽

High Carrier

Two-dimensional binary MX2 (M = Ni, Pd and Pt; X = P and As) exhibiting a beautiful pentagonal ring network is discussed through first principles calculations.

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First-Principle Study of Effect of Strain on the Band Structure of Germanane Monolayer

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.787.25 ◽

2018 ◽

Vol 787 ◽

pp. 25-30

Author(s):

Lei Liu ◽

Yan Ju Ji ◽

Yi Fan Liu

Keyword(s):

Band Structure ◽

Band Gap ◽

First Principles ◽

Density Functional ◽

Catalytic Properties ◽

Significant Implication ◽

First Principle ◽

First Principles Calculations ◽

Biaxial Strain ◽

Functional Theory

The effect of strain on the band structure of the GeH monolayer has been investigated by first-principles calculations based on density functional theory. The results show that the change of the band gap under the zigzag strain, the armchair strain and the biaxial strain is nonlinear. The effect of the biaxial strain on the band gap is the most obvious. In addition, the changes of energy under the three kinds of strain are asymmetric and the biaxial strain make the energy change the most. This work has significant implication of strain to tune optical catalytic properties of GeH monolayer.

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Penta-C20: A Superhard Direct Band Gap Carbon Allotrope Composed of Carbon Pentagon

Materials ◽

10.3390/ma13081926 ◽

2020 ◽

Vol 13 (8) ◽

pp. 1926 ◽

Cited By ~ 13

Author(s):

Wei Zhang ◽

Changchun Chai ◽

Qingyang Fan ◽

Yanxing Song ◽

Yintang Yang

Keyword(s):

Band Gap ◽

Mechanical Anisotropy ◽

Ab Initio Molecular Dynamics ◽

Structure Stability ◽

First Principles Calculations ◽

Carbon Allotrope ◽

Direct Band Gap ◽

Direct Band ◽

Promising Application ◽

First Time

A metastable sp3-bonded carbon allotrope, Penta-C20, consisting entirely of carbon pentagons linked through bridge-like bonds, was proposed and studied in this work for the first time. Its structure, stability, and electronic and mechanical properties were investigated based on first-principles calculations. Penta-C20 is thermodynamically and mechanically stable, with equilibrium total energy of 0.718 and 0.184 eV/atom lower than those of the synthesized T-carbon and supercubane, respectively. Penta-C20 can also maintain dynamic stability under a high pressure of 100 GPa. Ab initio molecular dynamics (AIMD) simulations indicates that this new carbon allotrope can maintain thermal stability at 800 K. Its Young’s modulus exhibits mechanical anisotropy. The calculated ideal tensile and shear strengths confirmed that Penta-C20 is a superhard material with a promising application prospect. Furthermore, Penta-C20 is a direct band gap carbon based semiconducting material with band gap of 2.89 eV.

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