Effect of composition variations on electrical and optical properties of La1-x(Ca,Sr)(x)MnO3 thin films

Thin pms of La0.67Ca0.33MnO3+delta (d approximate to 200 nm) grown at 750 d egrees C on MgO(100) substrates by pulsed laser deposition were annealed in various oxygen atmospheres. The LaF3, CaF2 and Mn overlayers (d approximat e to 5-10 nm) have been evaporated onto the films in order to saturate the compound by La, Ca or Mn during subsequent annealing at 900 degrees C in ai r. Further, the pulsed injection CVD method has been utilized to prepare se ries of La1-xSrxMnO3 films with x = 0 divided by 0.5 on LaAlO3(100). The ef fect of composition variations on electrical resistivity and magnetoresista nce of the films as well as on their optical transmission and reflection sp ectra in the energy range between 0.2 and 4.0 eV has been investigated.