High-temperature superconductivity with d-wave symmetry of the order parameter

It has been established as a result of successful direct experimental studi es of the symmetry of the superconducting order parameter that the pairing symmetry in the compounds YBCO, GdBCO, Tl2201, and Bi2212 is of the d-wave type. In this paper, experimental and theoretical results concerning the d- wave superconducting state and the peculiarities of magnetic properties of the d-type superconductor such as pseudogap, charge ordering, and unusual s tructure of vortex excitations differing from that for s-states are analyze d. Several mechanisms of d-pairing and related microscopic theories are dis cussed and possible experiments for their verification are proposed. (C) 19 98 American Institute of Physics. [S1063-777X(98)00111-X].