Probing Single walled Carbon Peapod enclosing the smallest Fullerene (C 20 @SWNT) as a two terminal junction device 1,2,3Department
Milanpreet Kaur1, Ravinder Singh Sawhney2, Derick Engles3 of Electronics Technology, Guru Nanak Dev University, Amritsar, Punjab, India
1mkb1313@yahoo.com, 2sawhney_gndu@hotmail.com, 3derickengles@yahoo.com
(a)
(b) Figure : C20 fullerene enclosed in SWNT forming two terminal junction (a) Front view and (b) Side view .
Modeling and simulation was performed using Atomistic Tool Kit ATK 13.8.1 and its graphic user interface Virtual Nano Lab and investigations are for various applied biases of both polarities ranging from -2 volt to 2 volt with step size of ±0.2.
Abstract: A novel approach towards the study of the electrical properties of the Carbon Peapod as two terminal junction device is being presented in this paper. The Carbon Peapod was synthesised by the enclosing the smallest known fullerene, C20 within Single Walled Carbon Nano Tube (SWNT), which was then perused as the two- probe molecular junction. Further, the two electrical properties namely, Current and Conductance were scrutinized through the detailed evaluation of its Density Of States (DOS), Molecular Energy Spectrum (MES) and Transmission Spectrum (TS) along with its comparison to the original Single Walled Carbon Nano Tube (SWNT). The C20 @SWNT Peapod junction exhibited the large deviations in Current characteristics from its aboriginal Armchair SWNT junction; which were clearly visible in detailed measurement characteristics- the Conductance Curve. Such a variation in the electrical characteristics was the indication of involvement of the enclosed fullerene in energy transfer process of this two-probe junction. We finally concluded that rigorous trapping of fullerene within SWNT could result in the applications for memory storage and processing. Keywords: Single Walled Nano Tube (SWNT), Non Equilibrium Green’s Function (NEGF), Extended Hückel Theory (EHT), Molecular electronics, Molecular orbitals (MOs) PACS: 73.63.-b , 85.65.+h 74.70.Wz
C20 @ SWNT
I-V CURVE
400
200
0
-200
-400 -2
APPROACH
For the prediction of transport properties, it is mandatory to study I-V characteristics and The current is computed using the Landauer–Buttiker formula
SWNT
Current (microAmperes)
In the present case, we encapsulated the smallest fullerene, C20 within the Single walled Carbon Nanotube in two probe configuration
CONSEQUENCES AND DELIBERATION
ABSTRACT
HOMO-LUMO at Zero Bias
SWNT C20@SWNT
-1
0
Applied Bias (Volts)
1
2
G-V CURVE
160
Conductance (MicroSiemens)
MODELLING AND SIMULATION
140
120
HOMO=-1.585474e-01 eV
where Tσ(E) is the transmission probability, f is the Fermi function, EFL is the fermi energy and TL and TR are the electron temperatures of the left and right electrodes, respectively.
LUMO=7.721168e-02eV
100 -2
SWNT C20@SWNT
-1
0
Applied Bias (Volts)
1
2