We show that narrow superconducting strips in superconducting (S) and normal (N) states are universally described by the model presenting them as lateral NSN proximity systems in which the superconducting central band is sandwiched between damaged edge bands with suppressed superconductivity. The width of the superconducting band was experimentally determined from the value of magnetic field at which the band transits from the Meissner state to the static vortex state. Systematic experimental study of 4.9-nm-thick NbN strips with widths in the interval from 50 nm to 20 μm, which are all smaller than the Pearl's length, demonstrates gradual evolution of the temperature dependence of the critical current with the change of the strip width.

中文翻译：

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超窄NbN带的邻近效应模型

我们显示，模型将超细的超导带普遍地描述为横向NSN邻近系统，该超导带处于超导（S）和正常（N）状态，其中超导中心带夹在受损的边缘带之间，并具有抑制的超导性。超导带的宽度是根据磁场从迈斯纳状态跃迁到静态涡旋状态时的磁场值实验确定的。对宽度在50 nm至20μm之间，宽度均小于Pearl长度的4.9 nm厚NbN条的系统实验研究表明，随着条宽的变化，临界电流对温度的依赖性逐渐​​提高。