Anomalous magnetoresistance in detwinned EuFe2As2*

Abstract

The in-plane magnetotransport of detwinned EuFe2As2 single crystal has been investigated. In the antiferromagnetic phase of Eu2+ spins, very different magnetoresistance results are observed upon the change of the external magnetic field direction and the current direction. This could be attributed to the tunable orientation of the Eu2+ spins under magnetic field. Electron scattering by spin fluctuation, superzone boundary effect, and cyclotron motion of charge carriers are used to interpret the observed anomalous magnetoresistance which is measured by using a current along a direction. The remarkable features of magnetoresistance suggest that itinerant electrons strongly couple with the spin configuration of Eu2+, which has a huge influence on the transport properties of EuFe2As2.