Resistive state anomalies of superconducting nanostructuresстатья
Информация о цитировании статьи получена из
Scopus,
Web of Science
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 18 июля 2013 г.
Аннотация:The V(T,I,H) characteristics have been measured for various multi-probe aluminium nanostructures. For several samples (pairs of voltage probes) the resistance at the top of the R(T) dependence can increase the corresponding normal state value. The effect is not fully reproducible, being dependent upon the cooling history. The magnitude of the resistance ‘bump’ can be reduced by a strong measuring current and/or by an external magnetic field. Two models have been proposed to explain the observed phenomena. Both models involve the existence of the N/S interface within the resistive transition. The inevitably formed N/S boundary potential step gives rise to additional resistance at the interface. For a static model, the formation of the N/S boundary is purely determined by the distribution of imperfections in the sample, while for a dynamic one, the N/S interface is periodically established with the average frequency of the thermal fluctuations Gamma and relaxes during the quasiparticle relaxation time tau(Q*). Both models could give the ‘order of magnitude’ agreement with the experiment, while the static one is simpler. The bad reproducibility of the experimental results (dependence upon the cooling history) is attributed to the dramatic sensitivity of the mesoscopic-size samples transport properties to the displacement of a few impurity atoms. (C) 1997 Academic Press Limited.