Transport and optical properties of epitaxial Nd1.83Ce0.17Cu04??thin films

Electrical transport measurements and transient optical pump-probe experiments have been performed on epitaxial films of the electron doped Nd 1.83Ce0.17Cu4-δ compound for studying the non-equilibrium carrier dynamics in this material. Samples have been grown on (001)-oriented SrTiO3 substrates by dc sputtering in a mixed atmosphere of both Ar and O2. X-ray diffraction analysis and scanning electron microscope equipped with a wavelength dispersive spectroscopy detector have been used to characterize the structure and the composition of the thin films. Time-resolved femtosecond pump-and-probe spectroscopy has been also carried out on our samples in the temperature range 4.2K-300 K.