Chabanenko Viktor, Nabiałek Adam, Puźniak Roman, Kuchuk Olena, Chumak Oleksandr, Pérez-Rodríguez Felipe, Pal Umapada, Garcia-Vazquez Valentin, Cortés-Maldonado Raul, Qian Jun, Yao Xin, Szymczak Henryk
O. Galkin Donetsk Institute for Physics and Engineering, NASU, Pr. Nauki 46, 03680, Kyiv, Ukraine.
Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, PL-02668, Warsaw, Poland.
Sci Rep. 2019 Apr 17;9(1):6233. doi: 10.1038/s41598-019-42699-5.
Experimental evidence of tremendous magnetic moment dynamical inversion, from metastable trapping state to the state with essentially the same moment oriented in the opposite direction, appearing during giant flux jump connected to thermomagnetic avalanche process in superconducting YBaCuO single crystal, is presented. Magnetization inversion takes place in the system, without thermal contact between sample and sample holder, with a tremendous stored energy once the avalanche process is completed in quasi-adiabatic conditions. A model of magnetic moment inversion, caused by the jump between two metastable states of superconductor with the same energy storage, is presented and discussed in terms of the critical state with peculiar evolution of the critical-current spatial distribution. Importantly, knowledge of conditions of the appearance of such a phenomenon is crucial for applications of bulk superconductors as "permanent" magnets, for example, in superconducting levitation devices, etc.
本文给出了实验证据，证明在超导YBaCuO单晶中与热磁雪崩过程相关的巨大磁通跳跃期间，会出现巨大磁矩动态反转，即从亚稳态俘获状态转变为磁矩大小基本相同但方向相反的状态。在准绝热条件下，一旦雪崩过程完成，系统中就会发生磁化反转，此时样品与样品架之间没有热接触，且存储了巨大的能量。本文提出并讨论了一个磁矩反转模型，该模型认为磁矩反转是由具有相同储能的超导体的两个亚稳态之间的跳跃引起的，并根据具有临界电流空间分布特殊演化的临界状态进行了讨论。重要的是，了解这种现象出现的条件对于块状超导体作为“永久”磁体的应用至关重要，例如在超导悬浮装置等中。
