Doping-dependent Phase Diagram of LaO{\it M}As ({\it M}=V--Cu) and   Electron-type Superconductivity near Ferromagnetic Instability
  By first-principles calculations, we present a doping-dependent phase diagram of LaO{\it M}As ({\it M}=V--Cu) family. It is characterized as antiferromagnetic semiconductor around LaOMnAs side and ferromagnetic metal around LaOCoAs. Both LaOFeAs and LaONiAs, where superconductivity were discovered, are located at the borderline of magnetic phases. Extensive Fermi surface analysis suggests that the observed superconductivity is of electron-type in its origin. We discuss possible pairing mechanisms in the context of competing ferromagnetic phases found in this work and the ferromagnetic spin fluctuations. 
Gang Xu, Wenmei Ming, Yugui Yao, Xi Dai, Shouchen Zhang, and Zhong   Fang