Lynnyk Artem, Puzniak Roman, Shi Luchuan, Zhao Jianfa, Jin Changqing
Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, PL-02668 Warsaw, Poland.
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Materials (Basel). 2023 Jul 20;16(14):5111. doi: 10.3390/ma16145111.
The superconducting state properties of the CuBaCaCuO (Cu-1234) system, with a transition temperature as high as 117.5 K, were investigated. The ac magnetic susceptibility measurements confirmed a very sharp transition to the superconducting state. The upper critical field, , as high as 91 T, and the irreversibility field, , as high as 21 T at 77 K, were determined using dc SQUID magnetization measurements. The intragrain critical current density, , estimated from a magnetic hysteresis loop, is as high as 5 × 10 A/m in a self-generated magnetic field at 77 K. However, the intergrain critical current density in the studied material is smaller by four orders of magnitude due to very weak intergrain connections.
研究了转变温度高达117.5K的CuBaCaCuO（Cu-1234）体系的超导态特性。交流磁化率测量证实了向超导态的非常尖锐的转变。使用直流超导量子干涉器件（SQUID）磁化测量确定了高达91T的上临界场以及在77K时高达21T的不可逆场。根据磁滞回线估计，在77K的自生磁场中，晶粒内临界电流密度高达5×10 A/m。然而，由于晶粒间连接非常弱，所研究材料中的晶粒间临界电流密度小四个数量级。
