Interlayer spin-singlet pairing induced by magnetic interactions in an antiferromagnetic superconductor

Shimahara Hiroshi

Physical Review B - Condensed Matter and Materials Physics

It is shown that interlayer spin-singlet Cooper pairing is induced by magnetic interactions in a metallic antiferromagnet of stacked conductive layers in which each layer is ferromagnetically polarized and they order antiferromagnetically in stacking direction. As a result, the antiferromagnetic long-range order and superconductivity coexist at low temperatures. It is shown that TAF>Tc except for in a very limited parameter region unless TAF=0, where TAF and Tc denote the antiferromagnetic and superconducting transition temperatures, respectively. It is found that the exchange field caused by the spontaneous staggered magnetization does not affect superconductivity at all, even if it is very large. The resultant superconducting order parameter has a horizontal line node, and is isotropic in spin space in spite of the anisotropy of the background magnetic order. We discuss the possible relevance of the present mechanism to the antiferromagnetic heavy fermion superconductors UPd2Al3 and CePt3Si.

Physics [ 420 ]

eng

American Physical Society

Copyright (c) 2000 The American Physical Society

[ISSN] 1098-0121

[DOI] http://dx.doi.org/10.1103/PhysRevB.61.R14936 isVersionOf