Electrical transport and carrier density collapse in doped manganite thin films

Based on the current-carrier-density-collapse theory, an expression is proposed for resistivity as a function of temperature and magnetic field. Our low-temperature resistivity data on high-quality epitaxial thin films of doped Mn oxides can be well fitted by the derived equation. At temperatures above Tc , the zero-field resistivity data can be also well explained by the carrier-density-collapse model. Moreover, the features of electrical transport in doped Mn oxides such as a dominant T dependence of low-temperature resistivity, and a strong H dependence of magnetoresistance at temperatures above Tc ar successfully interpreted in accordance with our deduction. We provide strong evidence to support that the carrier-density collapse can well describe the electrical transport in doped manganites.