Magnetic and electrical transport properties of YbFe2O4

Abstract

We present magnetic and electrical transport properties such as resistivity, magnetoresistance, dielectric, and polarization of polycrystalline ${\mathrm{YbFe}}_{2}{\mathrm{O}}_{4}$. The ferrimagnetic transition temperature is measured at 243 K, followed by the two low-temperature transitions at $\ensuremath{\sim}190$ and $\ensuremath{\sim}65$ K, respectively. The magnetic properties including the $M\ensuremath{-}H$ hysteresis loops exhibit a strong temperature dependence and possibly indicate a spin-glass state below 65 K for ${\mathrm{YbFe}}_{2}{\mathrm{O}}_{4}$. The iron M\"ossbauer measurement at 295 K confirms the presence of two Fe sites. The measured resistivity can be modeled with the Mott's variable-range hopping model, $\ensuremath{\rho}\ensuremath{\propto}exp{({T}_{0}/T)}^{1/4}$, indicating the electron hopping between ${\mathrm{Fe}}^{2+}$ and ${\mathrm{Fe}}^{3+}$ sites. The magnetoresistance effects up to 6% at 8 T were observed and the effects could be caused by the field-induced changes in the electron-hopping processes. The frequency-dependent complex dielectric constant has been found to be strongly influenced by the contact effects, and the polarization of polycrystalline ${\mathrm{YbFe}}_{2}{\mathrm{O}}_{4}$ does not show ferroelectricity.