Structural and Magnetic Characterization of Fe-doped La$_{2/3}$Ca$_{1/3}$MnO$_{3}$ Films

We have investigated pure and $^{57}$Fe-doped La$_{2/3}$Ca$_{1/3}$MnO$_{3}$ thin films, which were prepared via high O$_{2}$-pressure (500~mTorr) by magnetron DC sputtering on (100)~LaAlO$_{3}$, (100)~SrTiO$_{3}$ and (100)~MgO substrates. The $^{57}$Fe-doped samples contained 1\% and 3\% $^{57}$Fe per Mn. The structural and magnetic properties of the films and targets were characterized using X-ray diffraction(XRD) and reflectivity, M\"{o}ssbauer spectroscopy and magnetometry measurements. XRD shows that films are single phase and epitaxially oriented, and have negligible structural changes upon $^{57}$Fe-doping. The M\"{o}ssbauer spectra measured at room temperature exhibit one doublet with an isomer shift of 0.320$\pm$0.003~mms$^{-1}$, indicating the presence of the Fe$^{3+}$ ion at room temperature in the sample, which is a typical value of the high-spin of Fe$^{3+}$ with octahedral coordination. The quadrupole splitting value was 0.210$\pm$0.006~mms$^{-1}$. This clearly indicates that Fe is incorporated into the structure by substituting Mn. We will furthermore discuss the influence of $^{57}$Fe-doping on magnetic and magnetotransport properties.