The resonance tunneling process in the scanning tunneling microscope with carbon nanotube as a tip

الملخص EN

In our work we present an integrated calculation model to investigate the possibility of using carbon nanotubes as a tip for the scanning tunneling microscope.

Our model takes into consideration the electronic properties of the substrate and tip that fabricated by using carbon nanomaterials .

since we calculated the hybridization function and the quantum shift(as well as the assistant function) due to coupling between the molecule and the tip and the substrate .

This calculation are utilized to calculate the local density of states on the molecule .

We firstly studied the effect of all the properties of the carbon nanotube tip , since different carbon nanotubes chiral and achiral , metallic and semiconductor with different diameters are considered .

Also , we calculated the transport properties for the used system (substrate - molecule – carbon nanotube tip) , these calculations can be considered as an additional step to enhance our results .

We conclude that the carbon nanotube tip is not suitable for investigation in the most cases ,since that depends on the molecule effective energy level position with respect to the Van Hove (V.H) singularities in the electronic density of states of the carbon nanotube .

And as the normal distance between the tip and the molecule is one of the most important experimental parameters that enhance the process of investigation , the effect of the tip distance on the process of investigation is studied for the carbon nanotube (12,0) .

According to our calculations , it's concluded that it is possible to get the exact density of states by controlling the distance which is a function of the molecule effective energy level position