Effect of Ag addition on the magnetic and electrical properties of La0.67Ca0.33MnO3 films

Abstract La 0.67 Ca 0.33 MnO 3 :mol%Ag x (LCMO:Ag x , x  = 0, 0.04, 0.08, 0.10 and 0.20) films were prepared on the single crystalline (1 0 0)-orientated (LaAlO 3 ) 0.3 –(SrAlTaO 6 ) 0.7 (LSAT) substrates by the pulsed laser deposition (PLD) method. With the increasing of Ag addition, the magnetoresistance (MR) of the LCMO:Ag x films exhibits a significant decrease and the x  = 0 sample reach to the maximum value of MR ratio at 46.6% under 1 T magnetic field, in addition, the metal–insulator transition temperature ( T p ) improve 20–26 K or 12–18 K for the films at a zero or 1 T fields, respectively. The results maybe due to the fact that Ag enter the host lattice, partially substitute for La 3+ /Ca 2+ ion, and then increase the Mn 4+ /Mn 3+ ratio, which lead to enhance the electrical properties in LCMO:Ag x films.