F.V. Khan1, A.V. Khudchenko2, V.P. Koshelets3

1-4 Fryazino branch of Kotelnikov Institute of Radioengineering and Electronics of RAS (Fryazino, Russia)

Problem formulating. NbTiN is becoming the subject of interest because of unique properties in RF. Therefore, the problem of investigation of this material’s electrical properties rises sharply. 

Goal. This work is aimed at theoretical description of the superconductive films’ reflection coefficient with considering imaginary part of the superconductive gap and to apply the results to calculate the reflection coefficient from NbTiN film at frequencies up to 2500 GHz. 

Result. The formulas for calculation of the reflection coefficient with high precision was obtained. Parameters of NbTiN were calculated.

Practical meaning. Currently there are many factors which reduce the quality of NbTiN films and thus restricting their application. Therefore, the proposed method of calculations is useful in research activities in this area.

Khan F.V., Khudchenko A.V., Koshelets V.P. Application of the extended Mattis-Bardeen theory for the calculation of reflection coefficient of superconducting NbTiN thin films. Nonlinear World. 2021. V. 19. № 2. 2021. P. 52−56. DOI: https://doi.org/10.18127/j20700970-202102-12 (In Russian)

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