https://doi.org/10.1140/epjb/e2006-00027-y
Anomalous magnetoresistance in [Sr2Bi2-xPbxO4]RS[CoO2]y (x = 0, 0.3, and 0.4; y ≈ 1.85) single crystals
Hefei National
Laboratory for Physical Science at Microscale and Department of
Physics, University of Science and Technology of China, Hefei, Anhui
230026, P.R. China
Corresponding author: a chenxh@ustc.edu.cn
Received:
15
September
2005
Published online:
31
January
2006
Magnetoresistance (MR) of the [ Sr2Bi2-xPbxO4]RS[ CoO2] y (x = 0, 0.3, and 0.4; y ≈ 1.85; RS is referred to rocksalt block) single crystals is investigated systematically. A nonmonotonic variation of the isothermal in-plane and out-of-plane MR with the field is observed. The out-of-plane MR is positive at high temperatures and increases with decreasing T, and exhibits a pronounced hump, then changes the sign from positive to negative at a certain temperature. These results strongly suggest that the observed MR consists of two contributions: one negative and one positive component. The isothermal MR in high magnetic fields follows a H2 law. The negative contribution comes from spin scattering of carriers by localized-magnetic-moments based on the Khosla-Fischer model.
PACS: 75.47.-m – Magnetotransport phenomena; materials for magnetotransport / 71.30.+h – Metal-insulator transitions and other electronic transitions / 71.27.+a – Strongly correlated electron systems; heavy fermions
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2006