Light Emission Induced by the Indium Distribution in InGaN Nanowires

The InGaN nanowires (NWs) have attracted intense attention for their huge potential in applications such as light emitting diodes, laser diodes and solar cells. Although lots of work are focused on improving their optical performance, little is known about the influence of the In distribution and the surface states on the microscopic light emission mechanism. In order to give an atomic level understanding, we investigate the electronic structures of the wurtziteGa-rich InGaN NWs with different In distributions using first-principles calculations. We find that the In-atoms are apt to distribute on the surface of the NWs and the short surface In-N chains can be easily formed. For the unsaturated NWs, several new bands are induced by the surface states, which can be modified by the surface In microstructures. The randomly formed surface In-N chains can highly localize the electrons/holes at the band edges and dominate the interband optical transition. For the saturated NWs, the band edges are determined by the inner atoms. Our work is useful to improve the performance of the InGaN NW-based optoelectronic devices.

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Electronic structures and ferromagnetism of 3C-SiC doped with (Fe, Co) double-impurities by first-principles calculations

Materials Science in Semiconductor Processing ◽

10.1016/j.mssp.2021.105779 ◽

2021 ◽

Vol 129 ◽

pp. 105779

Author(s):

Long Lin ◽

Yujin Chen ◽

Hualong Tao ◽

Linwei Yao ◽

Jingtao Huang ◽

...

Keyword(s):

First Principles ◽

Electronic Structures ◽

First Principles Calculations

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Magnetism and electronic structures of bismuth (stannum) films at the CrI3 (CrBr3) interface

Physical Chemistry Chemical Physics ◽

10.1039/d0cp05531j ◽

2021 ◽

Vol 23 (7) ◽

pp. 4255-4261

Author(s):

Li Chen ◽

Chuan Jiang ◽

Maoyou Yang ◽

Tao Hu ◽

Yan Meng ◽

...

Keyword(s):

First Principles ◽

Electronic Structures ◽

First Principles Calculations

From first-principles calculations, the magnetism and electronic structures of bilayer bismuth (stannum) films at the monolayer CrI3 (CrBr3) interface are studied.

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Probing the electronic structures of Con (n = 1–5) clusters on γ-Al2O3 surfaces using first-principles calculations

Physical Chemistry Chemical Physics ◽

10.1039/c6cp06785a ◽

2017 ◽

Vol 19 (5) ◽

pp. 3679-3687 ◽

Cited By ~ 10

Author(s):

Tao Yang ◽

Masahiro Ehara

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Electronic Structures ◽

Density Functional ◽

Density Functional Theory Calculations ◽

First Principles Calculations ◽

Functional Theory

Using density functional theory calculations, we discussed the geometric and electronic structures and nucleation of small Co clusters on γ-Al2O3(100) and γ-Al2O3(110) surfaces.

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Stability and Structures of Constitutional Defects in Nonstoichiometric Intermetallic Compounds by First-Principles Calculations

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.3111 ◽

2005 ◽

Vol 475-479 ◽

pp. 3111-3114

Author(s):

Masataka Mizuno ◽

Hideki Araki ◽

Yasuharu Shirai

Keyword(s):

Intermetallic Compounds ◽

First Principles ◽

Electronic Structures ◽

Stoichiometric Composition ◽

Electronic Structure Calculations ◽

First Principles Calculations ◽

Compositional Dependence ◽

Wide Range ◽

Formation Energies ◽

Structure Calculations

Some of intermetallic compounds exist in a wide range of concentration around the stoichiometric composition. First-principles electronic structure calculations have been performed for constitutional defects in non-stoichiometric CoAl and CoTi in order to investigate their stabilities and structural relaxations induced by constitutional defects. For the evaluation of stabilities of constitutional defects, the compositional dependence curves both of formation energies and of lattice parameters are obtained by the calculations employing supercells in various sizes. The lattice relaxations around constitutional defects are discussed by analyzing the change in electronic structures induced by constitutional defects.

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First-Principles Calculations of Titanium Dopants in Alumina

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.3095 ◽

2005 ◽

Vol 475-479 ◽

pp. 3095-3098

Author(s):

Katsuyuki Matsunaga ◽

Teruyasu Mizoguchi ◽

Atsutomo Nakamura ◽

Takahisa Yamamoto ◽

Yuichi Ikuhara

Keyword(s):

Band Gap ◽

First Principles ◽

Electronic Structures ◽

First Principles Calculations ◽

Pseudopotential Calculations ◽

Formation Energies

First-principles pseudopotential calculations were performed to investigate atomic and electronic structures of titanium (Ti) dopants in alumina (Al2O3). It was found that a substitutional Ti3+ defect induced an extra level occupied by one electron within the band gap of Al2O3. When two or more substitutional Ti3+ defects were located closely to each other, the defect-induced levels exhibited strong bonding interactions, and their formation energies decreased with increasing numbers of Ti3+ defects. This indicates that association and clustering of substitutional Ti3+ defects in Al2O3 can take place due to the interaction of the defect-induced levels.

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Magnetism and Half-Metallicity in (100) Surface of Inverse Heusler Mn2CoSb

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1015.377 ◽

2014 ◽

Vol 1015 ◽

pp. 377-380

Author(s):

Tao Chen ◽

Ying Chen ◽

Yin Zhou ◽

Hong Chen

Keyword(s):

Density Functional Theory ◽

Magnetic Properties ◽

First Principles ◽

Heusler Alloy ◽

Density Functional ◽

Magnetic Moments ◽

Surface States ◽

First Principles Calculations ◽

Half Metallicity ◽

Functional Theory

Using the first-principles calculations within density functional theory (DFT), we investigated the electronic and magnetic properties of (100) surface of inverse Heusler alloy Mn2CoSb with five different terminations. Our work reveals that the surface Mn atom moves to vacuum while surface Co atom moves to slab. Moreover, duo to the reason that the surface atom lost half of the nearest atoms with respect to the bulk phase, resulting in the decrease of hybridization, the atom-resolved spin magnetic moments of surface atoms are enhanced. Further investigation on DOS and PDOS showed that half-metallicity was preserved only in SbSb-termination while was destroyed in MnCo-, MnSb-, MnMn-, and CoCo-termination due to the appearance of surface states.

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Phase stability and electronic structures of YbAl3−xMx (M=Mg, Cu, Zn, In and Sn) studied by first-principles calculations

Intermetallics ◽

10.1016/j.intermet.2009.04.008 ◽

2009 ◽

Vol 17 (12) ◽

pp. 995-999 ◽

Cited By ~ 13

Author(s):

Jian Zhou ◽

Zhimei Sun ◽

Xuan Cheng ◽

Ying Zhang

Keyword(s):

Phase Stability ◽

First Principles ◽

Electronic Structures ◽

First Principles Calculations

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Intriguing electronic structures and optical properties of two-dimensional van der Waals heterostructures of Zr2CT2 (T = O, F) with MoSe2 and WSe2

Journal of Materials Chemistry C ◽

10.1039/c7tc05963a ◽

2018 ◽

Vol 6 (11) ◽

pp. 2830-2839 ◽

Cited By ~ 29

Author(s):

Gul Rehman ◽

S. A. Khan ◽

B. Amin ◽

Iftikhar Ahmad ◽

Li-Yong Gan ◽

...

Keyword(s):

Optical Properties ◽

Material Properties ◽

First Principles ◽

Electronic Structures ◽

Van Der Waals ◽

Transition Metal Dichalcogenides ◽

Two Dimensional ◽

First Principles Calculations ◽

Van Der Waals Heterostructures ◽

Metal Dichalcogenides

Based on (hybrid) first-principles calculations, material properties (structural, electronic, vibrational, optical, and photocatalytic) of van der Waals heterostructures and their corresponding monolayers (transition metal dichalcogenides and MXenes) are investigated.

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Effect of Zn doping on phase transition and electronic structures of Heusler-type Pd2Cr-based alloys: from normal to all-d-metal Heusler

RSC Advances ◽

10.1039/d0ra02951c ◽

2020 ◽

Vol 10 (30) ◽

pp. 17829-17835

Author(s):

Xiaotian Wang ◽

Mengxin Wu ◽

Tie Yang ◽

Rabah Khenata

Keyword(s):

Phase Transition ◽

Electronic Structure ◽

First Principles ◽

Electronic Structures ◽

Heusler Alloys ◽

First Principles Calculations ◽

Zn Doping

By first-principles calculations, for Heusler alloys Pd2CrZ (Z = Al, Ga, In, Tl, Si, Sn, P, As, Sb, Bi, Se, Te, Zn), the effect of Zn doping on their phase transition and electronic structure has been studied in this work.

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Atomic and electronic structures of charge-doping VO2: first-principles calculations

RSC Advances ◽

10.1039/d0ra02420a ◽

2020 ◽

Vol 10 (32) ◽

pp. 18543-18552 ◽

Cited By ~ 2

Author(s):

Lanli Chen ◽

Yuanyuan Cui ◽

Hongjie Luo ◽

Yanfeng Gao

Keyword(s):

Phase Transition ◽

Transition Temperature ◽

Phase Transition Temperature ◽

First Principles ◽

Electronic Structures ◽

First Principles Calculations ◽

Charge Doping

The controllable phase transition temperature in charge doping VO2 is coupled with changes in the atomic and electronic structures. The current results provide a variable way to tune the VO2 phase transition temperature through charge doping.

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