Magneto-Superconductivity of Rutheno-Cuprates

Abstract

We reviewed our various results on rutheno-cuprate magneto-superconductors RuSr2GdCu2O8-d (Ru-1212) and RuSr2(Gd0.75Ce0.25)2Cu2O10-d (Ru-1222) synthesized by NPHT process. Also reviewed are the results for HPHT synthesized various Ln/Ru-1212, 1222 and 1232. Various important results being reported by other international groups are incorporated and discussed critically. It is observed, that it is difficult to control the oxygen content of Ru-1212, though the same is possible up to some extent for Ru-1222. Samples of both phases exhibited superconductivity, presumably in the CuO2 plane at low temperatures coexisting with magnetic ordering of Ru spins of predominantly antiferromagnetic type below 140 K having a ferromagnetic component appearing below 20 K. Electrical conductivity measurements indicate that the RuO2-d layer takes part in conduction besides the CuO2 plane. The magnetic ordering temperature of Ru spins is seen as a clear hump in the resistivity measurements, establishing the magnetic spins interaction with the conduction carriers.

28 pages of figs. and text. BOOK CHAPTER, Pubs. Springer Verlag Germany, Ed. A.V. Narlikar

References in corpus (10)

• Spin Glass Behavior in RuSr2Gd1.5Ce0.5Cu2O10
• Superconductivity in Ru(1-x)Sr2GdCu(2+x)O(8-y) Compounds
• Magnetic-Superconducting phase-diagram of Eu2-xCexRuSr2Cu2O10
• Ruthenocuprates RuSr2(Eu,Ce)2Cu2O10: Intrinsic magnetic multilayers
• Evidence for Possible Phase-Separations in RuSr2(Gd,Ce)2Cu2O10-delta
• On the effect of heterovalent substitutions in ruthenocuprates
• Magnetization study of RuSr2Y1.5Ce 0.5Cu2O10 (Ru-1222)
• Synthesis of RuSr2(Ln3/4Ce1/4)2Cu2O10 magneto-superconducting compounds with Ln = Ho, Y and Dy by high-pressure high-temperature (HPHT) technique
• Oxygen non-stoichiometry in Ru-1212 and Ru-1222 magnetosuperconductors
• Magneto-superconductivity of 100-atm O2-annealed RuSr2Gd1.5Ce0.5Cu2O10

Cited by in corpus (2)

• Magnetism, Upper critical field and Thermoelectric power of Magneto-Superconductor RuSr2Eu1.5Ce0.5Cu2O10
• Characteristic crossing point ($T_{\ast }\approx 2.7$ K) in specific-heat curves of samples RuSr${}_2$Gd${}_{1.5}$Ce${}_{0.5}$Cu${}_2$O${}_{10-\delta }$ taken for different values of magnetic field