In Fe pnictide (Pn) superconducting materials, neither Mn nor Cr doping to the Fe site induces superconductivity, even though hole carriers are generated. This is in strong contrast with the superconductivity appearing when holes are introduced by alkali-metal substitution on the insulating blocking layers. We investigate in detail the effects of Mn doping on magnetotransport properties in Ba(Fe1-xMnxAs)2 for elucidating the intrinsic reason. The negative Hall coefficient for x=0 estimated in the low magnetic field (B) regime gradually increases as x increases, and its sign changes to a positive one at x=0.020. Hall resistivities as well as simultaneous interpretation using the magnetoconductivity tensor including both longitudinal and transverse transport components clarify that minority holes with high mobility are generated by the Mn doping via spin-density wave transition at low temperatures, while original majority electrons and holes residing in the paraboliclike Fermi surfaces of the semimetallic Ba(FeAs)2 are negligibly affected. Present results indicate that the mechanism of hole doping in Ba(Fe1-xMnxAs)2 is greatly different from that of the other superconducting FePn family.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2015 May 11|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics