Tuning the electronic properties of monolayer and bilayer PtSe2via strain engineering

We utilize first principles calculations to investigate the mechanical properties and strain-dependent electronic band structure of the hexagonal phase of two dimensional (2D) HfS2. We apply three different deformation modes within −10% to 30% range of two uniaxial (D1, D2) and one biaxial (D3) strains along x, y, and x-y directions, respectively. The harmonic regions are identified in each deformation mode. The ultimate stress for D1, D2, and D3 deformations is obtained as 0.037, 0.038 and 0.044 (eV/Ang3), respectively. Additionally, the ultimate strain for D1, D2, and D3 deformation is obtained as 17.2, 17.51, and 21.17 (eV/Ang3), respectively. In the next step, we determine the second-, third-, and fourth-order elastic constants and the electronic properties of both unstrained and strained HfS2 monolayers are investigated. Our findings reveal that the unstrained HfS2 monolayer is a semiconductor with an indirect bandgap of 1.12 eV. We then tune the bandgap of HfS2 with strain engineering. Our findings reveal how to tune and control the electronic properties of HfS2 monolayer with strain engineering, and make it a potential candidate for a wide range of applications including photovoltaics, electronics and optoelectronics.

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Strain engineering and electric field tunable of the electronic properties of two-dimensional ZnGeN2 monolayer

New Journal of Chemistry ◽

10.1039/d1nj04760d ◽

2021 ◽

Author(s):

Thi Nga Do ◽

Son-Tung Nguyen ◽

Khang Pham

Keyword(s):

Electric Field ◽

Electronic Properties ◽

First Principles ◽

Strain Engineering ◽

Two Dimensional ◽

First Principles Calculations ◽

Structural And Electronic Properties

In this work, by means of the first-principles calculations, we investigate the structural and electronic properties of a two-dimensional ZnGeN2 monolayer as well as the effects of strains and electric...

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Equibiaxial Strained Oxygen Adsorption on Pristine Graphene, Nitrogen/Boron Doped Graphene, and Defected Graphene

Materials ◽

10.3390/ma13214945 ◽

2020 ◽

Vol 13 (21) ◽

pp. 4945

Author(s):

Li-Hua Qu ◽

Xiao-Long Fu ◽

Chong-Gui Zhong ◽

Peng-Xia Zhou ◽

Jian-Min Zhang

Keyword(s):

Electronic Properties ◽

First Principles ◽

Compressive Strain ◽

Oxygen Adsorption ◽

Strain Engineering ◽

Pristine Graphene ◽

First Principles Calculations ◽

Boron Doped ◽

Calculation Results ◽

Doped Graphene

We report first-principles calculations on the structural, mechanical, and electronic properties of O2 molecule adsorption on different graphenes (including pristine graphene (G–O2), N(nitrogen)/B(boron)-doped graphene (G–N/B–O2), and defective graphene (G–D–O2)) under equibiaxial strain. Our calculation results reveal that G–D–O2 possesses the highest binding energy, indicating that it owns the highest stability. Moreover, the stabilities of the four structures are enhanced enormously by the compressive strain larger than 2%. In addition, the band gaps of G–O2 and G–D–O2 exhibit direct and indirect transitions. Our work aims to control the graphene-based structure and electronic properties via strain engineering, which will provide implications for the application of new elastic semiconductor devices.

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UNIFORM BENDING EFFECT ON ELECTRONIC PROPERTIES OF BORON NITRIDE NANORIBBONS: A COMPUTATIONAL INVESTIGATION

Nano LIFE ◽

10.1142/s1793984412400053 ◽

2012 ◽

Vol 02 (02) ◽

pp. 1240005

Author(s):

YUNLONG LIAO ◽

ZHONGFANG CHEN

Keyword(s):

Boron Nitride ◽

Band Gap ◽

Electronic Properties ◽

First Principles ◽

Wide Band ◽

Band Gaps ◽

Computational Investigation ◽

Wide Band Gap ◽

Bending Effect ◽

Boron Nitride Nanoribbons

First-principles computations were performed to investigate the uniform bending effect on the electronic properties of armchair boron nitride nanoribbons (aBNNRs) with experimentally obtained width. For both bare and hydrogen-terminated aBNNRs, the band gaps only slightly depend on the uniform bending. The insensitivity of the band structures of BNNRs to the uniform bending makes them ideal materials when their wide band gap character is desired.

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Amorphous Semiconductors Studied by First-principles Simulations: Structure and Electronic Properties

MRS Proceedings ◽

10.1557/proc-1153-a04-03 ◽

2009 ◽

Vol 1153 ◽

Cited By ~ 1

Author(s):

Karol Jarolimek ◽

Robert A. de Groot ◽

Gilles A. de Wijs ◽

Miro Zeman

Keyword(s):

Band Gap ◽

Electronic Properties ◽

First Principles ◽

Density Functional ◽

Large Cell ◽

Band Gap Energy ◽

Amorphous Semiconductors ◽

Structural Defects ◽

Defect States ◽

Wide Range

AbstractAtomistic models of amorphous solids enable us to study properties that are difficult to address with experimental methods. We present a study of two amorphous semiconductors with a great technological importance, namely a- Si:H and a-SiN:H. We use first-principles density functional theory (DFT), i.e. the interatomic forces are derived from basic quantum mechanics, as only that provides accurate interactions between the atoms for a wide range of chemical environments (e.g. brought about by composition changes). This type of precision is necessary for obtaining the correct short range order. Our amorphous samples are prepared by a cooling from liquid approach. As DFT calculations are very demanding, typically only short simulations can be carried out. Therefore most studies suffer from a substantial amount of defects, making them less useful for modeling purposes. We varied the cooling rate during the thermalization process and found it has a considerable impact on the quality of the resulting structure. A rate of 0.02 K/fs proves to be sufficient to prepare realistic samples with low defect concentrations. To our knowledge these are the first calculations that are entirely based on first-principles and at the same time are able to produce defect-free samples. Because of the high computational load also the size of the systems has to remain modest. The samples of a-Si:H and a-SiN:H contain 72 and 110 atoms, respectively. To examine the convergence with cells size, we utilize a large cell of a-Si:H with a total of 243 atoms. As we obtain essentially the same structure as with the smaller sample, we conclude that the use of smaller cells is justified. Although creating structures without any defects is important, on the other hand a small number of defects can give valuable information about the structure and electronic properties of defects in a-Si:H and a-SiN:H. In our samples we observe the presence of both the dangling bond (undercoordinated atom) and the floating bond (over-coordinated atom). We relate structural defects to electronic defect states within the band gap. In a-SiN:H the silicon-silicon bonds induce states at the valence and conduction band edges, thus decreasing the band gap energy. This finding is in agreement with measurements of the optical band gap, where increasing the nitrogen content increases the band gap.

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Strain engineering of antimonene by a first-principles study: Mechanical and electronic properties

Physical Review B ◽

10.1103/physrevb.98.085410 ◽

2018 ◽

Vol 98 (8) ◽

Cited By ~ 35

Author(s):

Devesh R. Kripalani ◽

Andrey A. Kistanov ◽

Yongqing Cai ◽

Ming Xue ◽

Kun Zhou

Keyword(s):

Electronic Properties ◽

First Principles ◽

Strain Engineering ◽

First Principles Study

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Carbon phosphide nanosheets and nanoribbons: insights on modulating their electronic properties by first principles calculations

Physical Chemistry Chemical Physics ◽

10.1039/d0cp03615c ◽

2020 ◽

Vol 22 (39) ◽

pp. 22520-22528

Author(s):

Tong Chen ◽

Huili Li ◽

Yuyuan Zhu ◽

Desheng Liu ◽

Guanghui Zhou ◽

...

Keyword(s):

Band Gap ◽

Electronic Properties ◽

Electronic Transport ◽

First Principles ◽

Axial Strain ◽

Band Gaps ◽

First Principle ◽

First Principles Calculations ◽

Tunable Band Gap

We investigate the tunable band-gap semiconductor characteristics and electronic transport behaviors of 2D and quasi-1D CP derivatives by using first-principle methods. With bi-axial strain, the band gaps display an incremental trend from compression to stretching.

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First-principles Modeling of Structure, Vibrations, Electronic Properties and Bond Dynamics in Hydrogenated Amorphous Silicon: Theory versus Experiment

MRS Proceedings ◽

10.1557/proc-1153-a18-03 ◽

2009 ◽

Vol 1153 ◽

Author(s):

Anatoli Shkrebtii ◽

Ihor Kupchak ◽

Franco Gaspari

Keyword(s):

Amorphous Silicon ◽

Electronic Properties ◽

First Principles ◽

Hydrogen Diffusion ◽

Hydrogenated Amorphous Silicon ◽

Amorphous Structure ◽

Material Structure ◽

Electron Charge Density ◽

Wide Range ◽

Hydrogenated Amorphous

AbstractWe carried out extensive first-principles modeling of microscopic structural, vibrational, electronic properties and chemical bonding in hydrogenated amorphous silicon (a-Si:H) in a wide range of hydrogen concentration and preparation conditions. The theory has been compared with experimental results to comprehensively characterize this semiconductor material. The computer modeling includes ab-initio Molecular Dynamics (MD), atomic structure optimization, advanced signal processing and computer visualization of dynamics. We extracted parameters of hydrogen and silicon bonding, electron charge density and calculated electron density of states (EDOS) and hydrogen diffusion. A good agreement of the theory with various experiments allowed us to correlate microscopic processes at the atomic level with macroscopic properties. Here we focus on correlation of the amorphous structure of the material, atom dynamics and electronic properties. These results are of increasing interest due to extensive application of a-Si:H in modern research and technology and to the significance of detailed understanding of the material structure, bonding, disordering mechanisms and stability.

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The Structural and Electronic Properties of the Zigzag GaN Nanoribbons: A First-Principles Study

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.700.79 ◽

2013 ◽

Vol 700 ◽

pp. 79-82

Author(s):

Guo Xiang Chen ◽

Dou Dou Wang

Keyword(s):

Electronic Properties ◽

First Principles ◽

Energy Region ◽

Single Layer ◽

Band Gaps ◽

First Principles Calculations ◽

Zigzag Edge ◽

Minority Spin ◽

Structural And Electronic Properties ◽

Semiconductor Character

We have performed the first-principles calculations onto the structural and electronic properties of GaN nanoribbons with zigzag edge (ZGaNNRs). The results show that, the lowest unoccupied conduction band (LUCB) and the highest occupied valence band (HOVB) are always separated, representing a semiconductor character for the ZGaNNRs. In addition, the majority and minority spin bands are fully superposition and therefore the ZGaNNRs are non-magnetic. As the nanoribbons width increase, band gaps of ZGaNNRs decrease monotonically and become close to their asymptotic limit of a single layer of GaN sheet. It is found that the fewer coordination number will lead the most electrons to range in higher energy region of the occupancy state.

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First-Principles Investigation of Structural, Elastic and Electronic Properties of Lanthanide Titanate Oxides Ln2TiO5

MRS Proceedings ◽

10.1557/opl.2011.544 ◽

2011 ◽

Vol 1298 ◽

Cited By ~ 2

Author(s):

Hui Niu ◽

Huiyang Gou ◽

Rodney C. Ewing ◽

Jie Lian

Keyword(s):

Electronic Properties ◽

First Principles ◽

Density Functional ◽

Functional Theory ◽

Shear Moduli ◽

Charge Densities ◽

Young’S Moduli ◽

Wide Range ◽

Densities Of States ◽

Complete Set

ABSTRACTSystematic first-principles calculations based on density functional theory were performed on a wide range of Ln2TiO5 compositions (Ln = La, Ce, Pr, Nd, Sm, Gd, Tb, Dy and Y) in order to understand the correlation between structural, elastic and electronic properties. A complete set of elastic parameters including elastic constants, Hill’s bulk moduli, shear moduli, Young’s moduli and Poisson’s ratio, were calculated. All Ln2TiO5 are ductile in nature, and analysis of densities of states and charge densities suggests that the oxide bonds are highly ionic.

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