The magnetoresistance and Hall effect in CeFeAsO: a high magnetic field study

TL;DR

This study investigates the magnetoresistance and Hall effect in CeFeAsO under high magnetic fields, revealing a robust structural transition and unconventional magnetic behavior that challenges the typical SDW model.

Contribution

The paper provides high-field measurements of CeFeAsO's electrical properties, showing the transition's robustness and suggesting a non-conventional magnetic state.

Findings

Large magnetoresistance develops below Ts

Hall resistivity deviates from linearity below Ts

Transition at Ts is unaffected by high magnetic fields

Abstract

The longitudinal electrical resistivity and the transverse Hall resistivity of CeFeAsO are simultaneously measured up to a magnetic field of 45T using the facilities of pulsed magnetic field at Los Alamos. Distinct behaviour is observed in both the magnetoresistance Rxx({\mu}0H) and the Hall resistance Rxy({\mu}0H) while crossing the structural phase transition at Ts \approx 150K. At temperatures above Ts, little magnetoresistance is observed and the Hall resistivity follows linear field dependence. Upon cooling down the system below Ts, large magnetoresistance develops and the Hall resistivity deviates from the linear field dependence. Furthermore, we found that the transition at Ts is extremely robust against the external magnetic field. We argue that the magnetic state in CeFeAsO is unlikely a conventional type of spin-density-wave (SDW).