Applied Surface Science, Vol.421, 866-869, 2017
Temperature dependence of optical constants of La0.7Sr0.3MnO3 thin films
La0.7Sr0.3MnO3 films were prepared on MgO substrates using direct current (DC) magnetron sputtering, and the optical indices ranging from ultraviolet to infrared wavelengths (0.03-5.0 eV) were evaluated using spectroscopic ellipsometry at sample temperatures between 278 K and 373 K. The free-carrier concentration and mobility were estimated using fitted parameters of the Drude term obtained from analysis of the ellipsometric angle spectra and DC electrical resistivity. The mobility decreased with increasing sample temperature up to similar to 320 K, which was nearly equal to the metal-insulator transition temperature of the film. The mobility became constant at higher temperatures, whereas the concentration was almost constant relative to the sample temperature. (C) 2017 Elsevier B.V. All rights reserved.
Keywords:La0.7Sr0.3MnO3;Optical indices;Spectroscopic ellipsometry;Free-carrier concentration;Mobility