Competition between magnetic order and superconductivity in Fe oxy-pnictides

We have microscopically investigated the interplay between magnetism (M) and superconductivity (SC) of the RFeAsO (1111) oxy-pnictide for R=La, Sm and Ce as a function of F doping, isoelectronic Fe/Ru substitution and external pressure. In contrast to earlier data, our results suggest a unique behaviour in different 1111 families at the M-SC crossover, showing a sharp crossover between the two types of order as a function of F doping [1-3]. In the optimally e$^-$-doped SmFe$_ {1-x}$Ru$_x$AsO$_{0.85}$F$_{0.15}$ compound, magnetic order appears in the FeAs layers for $0.1

To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2011.MAR.W26.13