Cuprates magnetic ordering

It should be noted here that the conclusion about s-wave nature of the SC order parameter is consistent with conclusion about s-wave symmetry of the SC order parameter in the bulk and d-wave symmetry at the surface of the sample of the cuprates [17]. It was noted in [17] that most conclusions about d-wave symmetry was obtained in experiments (e.g. ARPES ones) on the cuprates in which mainly surface phenomena have been used. In this sense, the resistive measurements on the cuprates (see, e.g. [4]) are essentially bulk in the nature. In addition, the electron scattering (in resistivity measurements) is sensitive to the spin disorder in the system (magnetic contribution in the electrical resistivity appears, see Sec.l). Moreover, the electron scattering permits probe not only static magnetic order but dynamical (short-lived) ones because of short characteristic times as compared e.g. with usual neutron scattering. 

Lately high-temperature superconductors with rare-earth ions in their structure have been widely investigated. These compounds are based on antiferromagnetic dielectrics (yttrium-barium cuprates, cuprates of lanthanum or neodimium, etc.) having a distinctive lamellar structure which defines the peculiarities of magnetic interactions and magnetic ordering in the system of rare-earth ions. 

Although several other types of exotic superconductors (e.g., organic superconductors, heavy-fermion f-electron superconductors, magnetically ordered superconductors, multinary rare-earth, actinide, and transition-metal superconductors) have been investigated intensely since 1986, the cuprate superconductors have received by far the most attention because the highest values of the superconducting critical temperature are found in this class of materials. Rare-earth and actinide elements are key constituents of many of the high-temperature cuprate superconductors and have played a prominent role in the development of the first and some of the more important cuprate superconductors. 

R 197 H.B. Brom and J. Zaanen, Magnetic Ordering Phenomena and Dynamic Fluctuation in Cuprate Superconductors and Insulating Nick-elates , p. 379... 

---