Improved electrical properties of La2/3Ba1/3MnO3:Ag0.04 thin films by thermal annealing

La_2/3Ba_1/3MnO₃:Ag_0.04 (LBMO:Ag_0.04) thin films were prepared on single crystalline (001)-orientated LaAlO₃ substrates by pulsed laser deposition technique. Thermal annealing with temperatures of 780, 800 and 820 °C has been investigated to improve electrical properties of the films. All the samples are shown along the (00l) orientation in rhombohedral structure with ( Roverline{3} c ) space group. With thermal annealing temperature increasing, insulator–metal transition temperature (T _p) and resistivity at T _p ( ( rho_{{T_{text{p}} }} ) ) of the epilayer reach optimal value of 288 K and 0.03 Ω·cm, respectively. The electrical properties improvement of the LBMO:Ag_0.04 films is due to an improved film crystallization, oxygen balance and photon scattering suppression. The fitting curves show that the region of ferro-magnetic metallic (FM, T < T _p) is fitted with grain/domain boundary, electron–electron and magnon scattering mechanism, as well as the region of para-magnetic insulating (PI, T > T _p) is fitted with adiabatic small polaron hopping mechanism.