Effect of strain on the magnetism of Fe-doped MoTe2 monolayer

First-principles calculation has been performed to investigate the effect of strain on the magnetic moment of Fe-doped MoTe2 monolayer. Our results show that the Fe-doped MoTe2 monolayer is semiconductor with the magnetic moment of 2.037 [Formula: see text]. By analyzing the density of states, we find that the magnetic moment is mainly contributed by the Fe atom. When the biaxial strain is applied along the layer, the results show that the magnetic moment is almost unchanged when the compressive strain is under 5% and tensile strain is under 7%. However, as the strain increases, the magnetic moment decreases to almost zero with compressive strain larger than 7%, and the magnetic moment begins to increase with the tensile strain larger than 8%, which indicates the different effects of compressive strain and tensile strain on the magnetism of Fe-doped MoTe2.

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Electronic properties of monolayer molybdenum dichalcogenides under strains

MRS Proceedings ◽

10.1557/opl.2015.466 ◽

2015 ◽

Vol 1726 ◽

Author(s):

J. Sugimoto ◽

K. Shintani

Keyword(s):

First Principles ◽

Tensile Strain ◽

Compressive Strain ◽

Band Gaps ◽

First Principles Calculation ◽

Honeycomb Lattice ◽

Biaxial Strain ◽

Electronic Band ◽

Zigzag Direction ◽

Electronic Band Structures

ABSTRACTThe electronic band structures of monolayer molybdenum dichalcogenides, MoS2, MoSe2, and MoTe2 under either uniaxial or biaxial strain are calculated using first-principles calculation with the GW method. The imposed uniaxial strain is in the zigzag direction in the honeycomb lattice whereas the imposed biaxial strain is in the zigzag and armchair directions. It is found that the band gaps of these dichalcogenides almost linearly increase with the decrease of the magnitude of compressive strain, reach their maxima at some compressive strain, and then decrease almost linearly with the increase of tensile strain. It is also found their maximum band gaps are direct bandgaps.

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Strain Dependence of Energetics and Kinetics of Vacancy in Tungsten

Materials ◽

10.3390/ma13153375 ◽

2020 ◽

Vol 13 (15) ◽

pp. 3375

Author(s):

Zhong-Zhu Li ◽

Yu-Hao Li ◽

Qing-Yuan Ren ◽

Fang-Fei Ma ◽

Fang-Ya Yue ◽

...

Keyword(s):

Binding Energy ◽

First Principles ◽

Tensile Strain ◽

Kinetic Monte Carlo ◽

Compressive Strain ◽

Biaxial Strain ◽

Poisson Effect ◽

Vacancy Clusters ◽

Object Kinetic Monte Carlo ◽

Kinetic Monte Carlo Simulations

We investigate the influence of hydrostatic/biaxial strain on the formation, migration, and clustering of vacancy in tungsten (W) using a first-principles method, and show that the vacancy behaviors are strongly dependent on the strain. Both a monovacancy formation energy and a divacancy binding energy decrease with the increasing of compressive hydrostatic/biaxial strain, but increase with the increasing of tensile strain. Specifically, the binding energy of divacancy changes from negative to positive when the hydrostatic (biaxial) tensile strain is larger than 1.5% (2%). These results indicate that the compressive strain will facilitate the formation of monovacancy in W, while the tensile strain will enhance the attraction between vacancies. This can be attributed to the redistribution of electronic states of W atoms surrounding vacancy. Furthermore, although the migration energy of the monovacancy also exhibits a monotonic linear dependence on the hydrostatic strain, it shows a parabola with an opening down under the biaxial strain. Namely, the vacancy mobility will always be promoted by biaxial strain in W, almost independent of the sign of strain. Such unexpected anisotropic strain-enhanced vacancy mobility originates from the Poisson effect. On the basis of the first-principles results, the nucleation of vacancy clusters in strained W is further determined with the object kinetic Monte Carlo simulations. It is found that the formation time of tri-vacancy decrease significantly with the increasing of tensile strain, while the vacancy clusters are not observed in compressively strained W, indicating that the tensile strain can enhance the formation of voids. Our results provide a good reference for understanding the vacancy behaviors in W.

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First-principles study of the stability of silicane and germanane under strain

Modern Physics Letters B ◽

10.1142/s0217984914501383 ◽

2014 ◽

Vol 28 (17) ◽

pp. 1450138 ◽

Cited By ~ 3

Author(s):

T. Y. Du ◽

J. Zhao ◽

G. Liu ◽

J. X. Le ◽

B. Xu

Keyword(s):

First Principles ◽

Lattice Dynamics ◽

Density Functional ◽

Tensile Strain ◽

Helmholtz Free Energy ◽

Compressive Strain ◽

Specific Capacity ◽

Biaxial Strain ◽

Functional Theory ◽

The Stability

In this paper, we investigate the structural stability of silicane and germanane under biaxial strain by employing the lattice dynamics calculations within the frame of density functional theory. Our results show that silicane and germanane become unstable even under 1% compressive strain, while maintaining stable under tensile strain. Further calculations about the thermodynamical properties of silicane and germanane show that the phonon contribution to Helmholtz free energy, entropy and specific capacity are insensitive to the tensile strain.

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A FIRST-PRINCIPLES CALCULATION OF THE MAGNETIC MOMENT AND ELECTRONIC STRUCTURE FOR SELECTED HALF-HEUSLER ALLOYS

Modern Trends in Physics Research ◽

10.1142/9789814317511_0005 ◽

2011 ◽

Author(s):

SAMY H. ALY ◽

RIHAM SHAPARA ◽

SHERIF YEHIA

Keyword(s):

Electronic Structure ◽

Magnetic Moment ◽

First Principles ◽

Heusler Alloys ◽

First Principles Calculation

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First-principles calculation of the configurational energy density of states for a solid-state ion conductor with a variant of the Wang and Landau algorithm

Physical Review E ◽

10.1103/physreve.102.063304 ◽

2020 ◽

Vol 102 (6) ◽

Author(s):

Jason D. Howard

Keyword(s):

Solid State ◽

Energy Density ◽

Density Of States ◽

First Principles ◽

First Principles Calculation ◽

Configurational Energy ◽

Ion Conductor

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First-principles study of electronic structure, chemical bonding and elastic properties for new superconductor CaFeAs2

International Journal of Modern Physics B ◽

10.1142/s0217979216502635 ◽

2017 ◽

Vol 31 (02) ◽

pp. 1650263

Author(s):

J. G. Yan ◽

Z. J. Chen ◽

G. B. Xu ◽

Z. Kuang ◽

T. H. Chen ◽

...

Keyword(s):

Electronic Structure ◽

Elastic Properties ◽

Density Of States ◽

First Principles ◽

Elastic Anisotropy ◽

First Principles Calculation ◽

Hard Material ◽

Dirac Cone ◽

First Time ◽

New Superconductor

Using first-principles calculation we investigated the structural, electronic and elastic properties of paramagnetic CaFeAs2. Our results indicated that the density of states (DOS) was dominated predominantly by Fe-3[Formula: see text] states at Fermi levels, and stronger hybridization exists between As1 and As1 atoms. Three hole pockets are formed at [Formula: see text] and Z points, and two electronic pockets are formed at A and E points. The Dirac cone-like bands appear near B and D points. For the first time we calculated the elastic properties and found that CaFeAs2 is a mechanically stable and moderately hard material, it has elastic anisotropy and brittleness, which agrees well with the bonding picture and the calculation of Debye temperature ([Formula: see text]).

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