NMR Studies of Magnetic Vortex Cores of Type-II Superconductors

我们从原位和非原位NMR的角度发展了择位NMR技术，研究了II型超导体混合态中涡旋核内量子干涉束缚态的局域磁性，发现了Ca_（2-x）Na_xCuO_2Cl_2的非均匀磁关联，这是Hg_（1223）超导转变时的磁分异现象，以及Bi 2212在T_c以下的宽NQR谱中自旋关联的频率分布。

We have developed site-selective NMR techniques from the viewpoints of In-situ and Ex-situ NMR to study the local magnetism of quantum interference bound states inside vortex cores in the mixed states of type II superconductors.We found the inhomogeneous magnetic correlation of Ca_2-xNa_xCuO_2Cl_2, a magnetic differentiation phenomenon at the superconducting transition for Hg1223, and frequency distribution of spin correlation in the broad NQR spectrum of Bi2212 below T_c.