Possible re-entrant superconductivity in EuFe2As2 under pressure
  We studied the temperature-pressure phase diagram of EuFe2As2 by measurements of the electrical resistivity. The antiferromagnetic spin-density-wave transition at T_0 associated with the FeAs-layers is continuously suppressed with increasing pressure, while the antiferromagnetic ordering temperature of the Eu 2+ moments seems to be nearly pressure independent up to 2.6 GPa. Above 2 GPa a sharp drop of the resistivity, \rho(T), indicates the onset of superconductivity at T_c \approx 29.5 K. Surprisingly, on further reducing the temperature \rho(T) is increasing again and exhibiting a maximum caused by the ordering of the Eu 2+ moments, a behavior which is reminiscent of re-entrant superconductivity as it is observed in the ternary Chevrel phases or in the rare-earth nickel borocarbides. 
C. F. Miclea, M. Nicklas, H. S. Jeevan, D. Kasinathan, Z. Hossain, H.   Rosner, P. Gegenwart, C. Geibel, and F. Steglich