TY - JOUR
T1 - Mixed-state hall effect and flux pinning in Ba(Fe1-xCo x)2As2 single crystals (x=0.08 and 0.10)
AU - Wang, L. M.
AU - Sou, Un Cheong
AU - Yang, H. C.
AU - Chang, L. J.
AU - Cheng, Cheng Maw
AU - Tsuei, Ku Ding
AU - Su, Y.
AU - Wolf, Th
AU - Adelmann, P.
PY - 2011/4/7
Y1 - 2011/4/7
N2 - Longitudinal and Hall resistivities, scaling behavior, and magnetizations are examined to study the effect of flux pinning in Ba(Fe1-xCo x)2As2 (BFCA) single crystals with x=0.08 and 0.01. Larger values of activation energy, critical current density, and pinning force are obtained in BFCA with x=0.10, indicating relatively strong pinning. The sign reversal of Hall resistivities is clearly observed in BFCA with x=0.10. The correlation between longitudinal and Hall resistivities shows the scaling behavior of ρxy(ρxx)β with exponents β=3.0-3.4 and 2.0±0.2 for BFCA crystals with x=0.08 and 0.10, respectively. Furthermore, the normal-state Hall angle is also observed to follow cotθH=ΛT2+C in BFCA crystals, and is explained by the Anderson theory. The relatively large c/Λ value for BFCA with x=0.10 also implies a larger contribution of impurity scattering due to more Co atoms, which may cause stronger pinning of flux lines. The results are analyzed and coincide with theory, including the pinning-induced backflow effect and plastic flow mechanism in vortex dynamics.
AB - Longitudinal and Hall resistivities, scaling behavior, and magnetizations are examined to study the effect of flux pinning in Ba(Fe1-xCo x)2As2 (BFCA) single crystals with x=0.08 and 0.01. Larger values of activation energy, critical current density, and pinning force are obtained in BFCA with x=0.10, indicating relatively strong pinning. The sign reversal of Hall resistivities is clearly observed in BFCA with x=0.10. The correlation between longitudinal and Hall resistivities shows the scaling behavior of ρxy(ρxx)β with exponents β=3.0-3.4 and 2.0±0.2 for BFCA crystals with x=0.08 and 0.10, respectively. Furthermore, the normal-state Hall angle is also observed to follow cotθH=ΛT2+C in BFCA crystals, and is explained by the Anderson theory. The relatively large c/Λ value for BFCA with x=0.10 also implies a larger contribution of impurity scattering due to more Co atoms, which may cause stronger pinning of flux lines. The results are analyzed and coincide with theory, including the pinning-induced backflow effect and plastic flow mechanism in vortex dynamics.
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U2 - 10.1103/PhysRevB.83.134506
DO - 10.1103/PhysRevB.83.134506
M3 - Article
AN - SCOPUS:79961055421
SN - 1098-0121
VL - 83
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
IS - 13
M1 - 134506
ER -