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arXiv · 1711.04585

The role of Coulomb interaction in superconducting NbTiN thin films

D. Hazra·N. Tsavdaris·A. Mukhtarova·M. Jacquemin·F. Blanchet·R. Albert·S. Jebari·A. Grimm·E. Blanquet·F. Mercier·C. Chapelier·M. Hofheinz
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Abstract

We report on the superconducting properties of Nb$_{1-x}$Ti$_x$N thin films of thickness $\sim$ 10 nm, with different Ti fraction $x$ in the range $ 0 \leq x \leq 0.5$, deposited by high temperature chemical vapor deposition. In this parameter range, we observe that the superconducting critical temperature ($T_c$) increases with $x$. Our analysis, in accordance with both McMillan's and Finkelstein's theories, shows that disorder-enhanced Coulomb interaction decreases with $x$, leading to an increase of $T_c$.

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D. Hazra, N. Tsavdaris, A. Mukhtarova, M. Jacquemin, F. Blanchet, R. Albert, S. Jebari, A. Grimm, E. Blanquet, F. Mercier, C. Chapelier, M. Hofheinz. 2017-11-13. The role of Coulomb interaction in superconducting NbTiN thin films. https://doi.org/10.1103/physrevb.97.144518

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