Preparation and study of silver added La0.67Ca0.33MnO3 film

Abstract La 0.67 Ca 0.33 MnO 3 (LCMO) and Ag admixed La 0.67 Ca 0.33 MnO 3 (Ag–LCMO) polycrystalline films have been prepared on SrTiO 3 single crystal (100) substrates by ultrasonic spray pyrolysis technique. These films are characterized using XRD, SEM, and temperature dependence of resistivity ( ρ - T ) and ac susceptibility ( χ - T ). The films are having cubic structure with lattice parameters as 3.890 and 3.885 A for LCMO and Ag–LCMO films, respectively. The peek in ρ - T curve ( T p ) and the ferromagnetic transition temperature ( T C ) for the Ag-LCMO film is higher than that of LCMO film. The stability of both the films was tested by repeated measurements of its characteristics over a period of one week after several thermal cycling from room temperature to 77 K. In the LCMO film, the peak in the ρ - T curve ( T p ) is found to shift towards lower value and conduction noise of the film increases in the subsequent measurements. In the case of Ag–LCMO the value of T p , T C and conduction noise of the film did not change even after several measurements. Silver segregating at the grain boundaries in Ag–LCMO polycrystalline film seems to be responsible for improving the characteristics of Ag–LCMO films.