Direct observation of electron doping inLa0.7Ce0.3MnO3using x-ray absorption spectroscopy

We report an x-ray absorption spectroscopic (XAS) study on thin films of ${\mathrm{La}}_{0.7}{\mathrm{Ce}}_{0.3}{\mathrm{MnO}}_{3}.$ The measurements clearly show that the cerium is in the Ce(IV) valence state, and that the manganese is present in a mixture of ${\mathrm{Mn}}^{2+}$ and ${\mathrm{Mn}}^{3+}$ valence states. These data demonstrate that ${\mathrm{La}}_{0.7}{\mathrm{Ce}}_{0.3}{\mathrm{MnO}}_{3}$ is an electron-doped colossal magnetoresistive manganite, a finding that may open up opportunities for device applications as well as for further research on the colossal magnetoresistance phenomenon in these materials.