O.E. Glukhova – Dr.Sc.(Phys.-Math.), Professor, Head of the Department of Radiotechnique and Electrodynamics, Saratov National Research State University named after N.G. Chernyshevsky

E-mail: glukhovaoe@info.sgu.ru

K.R. Asanov – Post-graduate Student, 

Department of Radiotechnique and Electrodynamics, Saratov National Research State University named after N.G. Chernyshevsky

E-mail: asanov.k.93@mail.ru

At present, thin films in the form of regular X-shaped junctions of carbon nanotubes (CNTs) with various chirality are promising materials for optoelectronics and nanoelectronics. An important and not fully clarified issue is the evaluation of the dynamic conductivity of such carbon junctions. The purpose of this work is to build super-cells of thin films from X-shaped junctions based on metallic CNTs of various chirality with the subsequent study of their dynamic conductivity in the ultraviolet (UV) – visible – infrared (IR) wavelength range. During the study we created atomistic models of seamless X-shaped junctions of CNTs with chiralities (m, m), where m = 10, 12, 14, and (n, 0), where n = 18, 21, 24. The empirical Brenner potential and the quantum method SCC DFTB were used to create these models. The dynamic conductivity of the constructed atomistic models of X-shaped CNT junctions was calculated using the Kubo-Greenwood formula. It was found that during the formation of X-shaped CNT junctions the defects in the form of pentagons, heptagons and octagons are forming in the area of the joining of CNTs. It was shown for the first time that the maximum values of the dynamic conductivity of films of X-shaped CNT junctions, equal to 2.8…3.7, are in the ultraviolet range at wavelengths of ≈0.03…0.34 μm. In this case, the dynamic conductivity in the layers of X-shaped CNT junctions is almost independent of the direction of the incident electromagnetic wave, which is an undoubted advantage of such layers over layers of parallel-lying CNTs. It was revealed that the dynamic conductivity of films of X-shaped CNT junctions does not depend on the chirality of the CNTs forming them and the number of defects. On the basis of the obtained results, it can be concluded that 2D structures made of X-shaped CNT junctions are promising as a sensitive layer of the basic elements of optoelectronics devices.

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