FIRST-PRINCIPLES INVESTIGATION ON BAND STRUCTURE AND ELECTRONIC TRANSPORT PROPERTY OF GALLIUM NITRIDE NANORIBBON

NANO ◽  
2014 ◽  
Vol 09 (02) ◽  
pp. 1450020 ◽  
Author(s):  
R. CHANDIRAMOULI ◽  
S. SRIRAM

The electronic transport property and band structure of pure gallium nitride, oxygen, fluorine, indium substituted gallium nitride nanoribbon and defect structured GaN nanoribbons are investigated by employing first-principles studies using density functional theory. The band structure of pure GaN and indium substituted GaN nanoribbon shows a semiconducting nature. The oxygen, fluorine substituted GaN and defect structured GaN results in metallic behavior. The density of states provides the insight for the localization of charges in the valence band and conduction band. The substitution of oxygen and fluorine enhance the density of charges in valence band and conduction band. The substitution of indium shows an increase in the peak amplitude in density of states. The presence of defect also increases the density of states. The transport properties are studied in terms of transmission spectrum; pure GaN and indium substituted shows a same trend in transmission. In contrast, the transmission can be enhanced by the substitution of oxygen, fluorine and defect in nanoribbon. The information provided in the present study will pave its way to tailor a new material of GaN nanostructures with improved performance in the optoelectronic devices.

2009 ◽  
Vol 23 (19) ◽  
pp. 2339-2352 ◽  
Author(s):  
LI BIN SHI ◽  
SHUANG CHENG ◽  
RONG BING LI ◽  
LI KANG ◽  
JIAN WEI JIN ◽  
...  

Density of states and band structure of wurtzite ZnO are calculated by the CASTEP program based on density functional theory and plane-wave pseudopotential method. The calculations are carried out in axial and unaxial strains, respectively. The results of density of states in different strains show that the bottom of the conduction band is always dominated by Zn 4s, and the top of valence band is always dominated by O 2p. The variation of the band gap calculated from band structure is also discussed. In addition, p-d repulsion is used in investigating the variation of the top of the valence band in different strains and the results can be verified by electron density difference.


Micromachines ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 309
Author(s):  
Min Luo ◽  
Bin Yu ◽  
Yu-e Xu

First-principles calculations were used to investigate the electronic properties of the SiC/GeC nanosheet (the thickness was about 8 Å). With no electric field (E-field), the SiC/GeC nanosheet was shown to have a direct bandgap of 1.90 eV. In the band structure, the valence band of the SiC/GeC nanosheet was mainly made up of C-p, while the conduction band was mainly made up of C-p, Si-p, and Ge-p, respectively. Application of the E-field to the SiC/GeC nanosheet was found to facilitate modulation of the bandgap, regularly reducing it to zero, which was linked to the direction and strength of the E-field. The major bandgap modulation was attributed to the migration of C-p, Si-p, and Ge-p orbitals around the Fermi level. Our conclusions might give some theoretical guidance for the development and application of the SiC/GeC nanosheet.


2011 ◽  
Vol 1329 ◽  
Author(s):  
K. Xiong ◽  
S. Sobhani ◽  
R. P. Gupta ◽  
W. Wang ◽  
B. E. Gnade ◽  
...  

ABSTRACTWe investigate the impact of various dopants (Na, Ag, Cd, Zn, Al, Ga, In, Tl, Ge, and Sn) on the electronic structure of Mg2Si by first principles calculations using a hybrid functional that does not need a band gap correction. We find that for Na and Ge in Mg2Si, the impurity-induced states do not affect the density of states at both edges of the valence band and the conduction band. Ag- and Sn affect slightly the density of states at the valence band edge, while Cd and Zn affect slightly the density of state at the conduction band edge. Al and In could modify significantly the density of states at the conduction band edge. Ga introduces states just at the bottom of the conduction band. Tl introduces states in the band gap. This study provides useful information on optimizing the thermoelectric efficiency of Mg2Si.


CrystEngComm ◽  
2021 ◽  
Author(s):  
Sanjay Kumar ◽  
Soumen Singha ◽  
Rajkumar Jana ◽  
RITUPARNA MONDAL ◽  
Partha Pratim Bag ◽  
...  

Herein, we report the crystal structure, supramolecular structure, electronic transport property and optoelectronic behaviour of a co-crystal made of tetrabromoterephthalic acid (TBTA) and quinoxaline (QUIN) (1:1). The sample has been...


2011 ◽  
Vol 58 (4) ◽  
pp. 792-796 ◽  
Author(s):  
Hiroaki Yamada ◽  
Tadahiro Fukushima ◽  
Takeshi Yoshimura ◽  
Norifumi Fujimura

2005 ◽  
Vol 864 ◽  
Author(s):  
Salameh Ahmad ◽  
Daniel Bilc ◽  
S.D. Mahanti ◽  
M.G. Kanatzidis

AbstractAb initioelectronics structure calculations have been carried out in a series of RPb2n-1Te2n, n=16, compounds to understand the nature of “defect” states introduced by R where R = vacancy, monovalent Na, K, Rb, Cs, Ag atoms and divalent Cd atoms. We find that the density of states (DOS) near the top of the valence band and the bottom of the conduction band get significantly modified. The Na atom seems to perturb this region least (ideal acceptor in PbTe) and the other monovalent atoms enhance the DOS near the top of the valence band. Cd is an interesting case, since it introduces a strong resonance state near the bottom of the conduction band.


2018 ◽  
Vol 30 (11) ◽  
pp. 115001 ◽  
Author(s):  
Liwei Jiang ◽  
Lanting Feng ◽  
Haibo Yao ◽  
Yisong Zheng

2005 ◽  
Vol 105 (1-4) ◽  
pp. 293-298 ◽  
Author(s):  
Qunxiang Li ◽  
Xiaojun Wu ◽  
Jing Huang ◽  
Jinlong Yang

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