Inhomogeneous Electron Gas

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Transport properties of parallel carbon nanotubes
adhered by Pt atom
Ayumu Sugiyama1, Nguyen Thanh Cuong2, and Dam Hieu Chi1,2
1
School of Knowledge Sciences, Japan Advanced Institute of Science and Technology, 1-1
Asahidai, Nomi, Ishikawa, Japan
2
School of Materials Sciences, Japan Advanced Institute of Science and Technology, 1-1
Asahidai, Nomi, Ishikawa, Japan
3
Faculty of Physics, Hanoi University of Science, 334 Nguyen Trai, Thanh Xuan , Hanoi,
Vietnam
Carbon nanotubes(CNT) have attracted many researchers interest because of their electronic
variety based on their own unique and beautiful structures. Since the particular electronic
properties of CNT, such like metallic and semiconducting state of itself, are arise from not only
structural uniqueness but also atomic defect and atomic adsorption, controlling the electronic
character of CNT by atomic defect and atomic adsorption is one of significant issue to develop
the CNT devices. You should send the abstracts in the MS Word format. While other styles are
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References can appear as superscripts1 or in square brackets [1]. We recommend you to include
a figure summarizing your results. In the theoretical study, many number of researches have
been figure out the detail of electronic structure and chirality’s character of CNT by first
principle calculations. We also investigate the electronic properties of CNT from the relation
between CNT curvature and binding energy of Pt adsorption on CNT surface in term of d - π
hybridization of Pt - CNT. Due to the above researches have been making clear the physical
properties and electronic properties of CNT, in applying for nano devices, one of fundamental
problem is estimating the transport properties of nano devices. In nano scale, as the ballistic
electron transport is becoming dominating, devices fact a unavoidable problem by quantum
effect, which is different from common diffusive transport, caused by scale dependence
phenomena like nonlinear I-V character, quantized conductance.
These characters are proactive issues to make a nano device as alternative device of diffusive
electron device. Reentry, some theoretical development make it possible to estimate the
transport properties of nano scale region in the first principle treatment like LippmannSchwinger method, Nonequilibrium Green's function (NEGF) method and so on. They indicate
that transport properties are very sensitive and dramatically changed by contact structure. In
case of metallic CNTs, some researches indicate that the atomic defect on CNTs also release the
effect for transport properties, though there are no degradation in conductance around Fermi
level. As a result of research upon, metal adsorption CNTs involve the charge transfer such like
our previous study using Platinum atom are also interested in the study of more complex system
applying for nano devices.
In this study, we investigate the transport properties of (5,5) metallic single wall carbon
nanotubes (SWNTs) by first principle calculation with NEGF approach, which is one of suitable
method for studying the quantum transport phenomena of electrons in nano scale. Although it is
important to find the most fitting structure for electron transport, we adopt SWNT electrodes for
all calculations to neglect the interface between SWNTs and electrode. Then, we focus on the
transport properties of SWNT from the viewpoint of understanding how charge transfer effect
for transmission properties of SWNTs. At first, we confirm the adsorption effect by comparing
the pure (5,5) metallic SWNT and Pt atom adsorbed on (5,5) metallic SWNT. Next, we examine
three kind of parallel SWNTs case; parallel two SWNTs model, parallel two SWNTs adhered
by Pt atom model and parallel two SWNTs adhered by Pt atom with connected to electrode only
one side model. We would like to discuss the difference between single SWNT and parallel
SWNTs. Furthermore, we consider much more about recent one side electrode model. The
difference of current passway between each electrode, the current through the Pt atom and
tunneling current between SWNTs, has also made clear in this paper. Thus, we find the
fundamental dominant properties of nano scale transmission of metallic SWNTs.
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