Hall effect and resistivity study of the magnetic transition, carrier content, and fermi-liquid behavior in Ba(Fe1-xCox)2As2
Résumé
The negative Hall constant RH measured all over the phase diagram of Ba(Fe1-xCox)2As2 allows us to show that electron carriers always dominate the transport properties. The evolution of RH with x at low doping (x<2%) indicates that important band structure changes happen for x<2% prior to the emergence of superconductivity. For higher x, a change with T of the electron concentration is required to explain the low T variations of RH, while the electron scattering rate displays the T2 law expected for a Fermi liquid. The T=0 residual scattering is affected by Co disorder in the magnetic phase, but is rather dominated by incipient disorder in the paramagnetic state.