Author/Authors :
Shigeyuki Ishida، نويسنده , , Masamichi Nakajima MD، نويسنده , , Motoyuki Ishikado، نويسنده , , Yasuhide Tomioka، نويسنده , , Toshimitsu Ito، نويسنده , , Kiichi Miyazawa، نويسنده , , Chul-Ho Lee، نويسنده , , Hijiri Kito، نويسنده , , Shin-ichi Shamoto، نويسنده , , Akira Iyo، نويسنده , , Hiroshi Eisaki، نويسنده , , Kenji M. Kojima، نويسنده , , Teruhisa Kakeshita، نويسنده , , Shin-ichi Uchida، نويسنده ,
Abstract :
In order to reveal the role of “carrier doping” in the iron-based superconductors, we investigated the transport properties of the oxygen-deficient iron-arsenides LnFeAsO1−y (Ln=La, Ce, Pr and Nd) over a wide doping range. We found that the effect of “doping” in this system is mainly on the carrier scattering rather than carrier density, quite distinct from that in high-Tc cuprates. In the case of La system with lower Tc, the low temperature resistivity is dominated by T2 term and fairly large magnetoresistance is observed. On the other hand, in the Nd system with higher Tc, carriers are subject to stronger scattering showing nearly T-linear resistivity and small magnetoresistance. Such strong scattering appears intimately correlated with high-Tc superconductivity in the iron-based system.