Burdastyh M V, Postolova S V, Proslier T, Ustavshikov S S, Antonov A V, Vinokur V M, Mironov A Yu
A. V. Rzhanov Institute of Semiconductor Physics SB RAS, 13 Lavrentjev Avenue, Novosibirsk, 630090, Russia.
Novosibirsk State University, Pirogova str. 2, Novosibirsk, 630090, Russia.
Sci Rep. 2020 Jan 30;10(1):1471. doi: 10.1038/s41598-020-58192-3.
Suppression of superconductivity in disordered systems is a fundamental problem of condensed matter physics. Here we investigate superconducting niobium-titanium-nitride (NbTiN) thin films grown by the atomic layer deposition (ALD) with slightly different growth process parameters. We observe a smooth crossover from the disorder-driven superconductor-normal metal transition (SMT) to the superconductor-insulator transition (SIT) via the intermediate Bose metal state detected by the low-temperature saturation of the temperature dependence of the sheet resistance. We demonstrate that the SIT via the intervening Bose metal state occurs if the sheet resistance of the film in the maximum, R prior to the superconducting drop of R(T), exceeds R = h/4e.
无序系统中超导电性的抑制是凝聚态物理的一个基本问题。在此，我们研究了通过原子层沉积（ALD）生长的、生长工艺参数略有不同的超导铌钛氮（NbTiN）薄膜。我们观察到，通过薄层电阻温度依赖性的低温饱和检测到的中间玻色金属态，实现了从无序驱动的超导体-正常金属转变（SMT）到超导体-绝缘体转变（SIT）的平滑过渡。我们证明，如果薄膜在R(T)超导下降之前的最大薄层电阻R超过R = h/4e，则会通过中间玻色金属态发生SIT。
