## Kondo-like mass enhancement of Dirac fermion in iron pnictides Ba(Fe\$_{1-x}\$Mn\$_x\$As)\$_2\$    [PDF]

T. Urata, Y. Tanabe, K. K. Huynh, H. Oguro, K. Watanabe, S. Heguri, K. Tanigaki
The effect of Mn substitution, acting as a magnetic impurity for Fe, on the Dirac cone was investigated in Ba(Fe\$_{1-x}\$Mn\$_x\$As)\$_2\$. Both magnetoresistance and Hall resistivity studies clearly indicate that the cyclotron effective mass (\$m^{\ast}\$) of the Dirac cone is anomalously enhanced at low temperatures by the impurity, although its evolution as a function of carrier number proceeds in a conventional manner at higher temperatures. Kondo-like band renormalization induced by the magnetic impurity scattering is suggested as an explanation for this, and the anomalous mass enhancement of the Dirac fermions is discussed.
View original: http://arxiv.org/abs/1307.2813