MAGNETORESISTIVITY IN Y-LA-CA-MN-O THIN-FILMS

Thin films of Y0.07La0.60Ca0.33MnOx, have been prepared by pulsed lase r deposition onto LaAlO3(012) substrates at different laser repetition rates. Whereas at a rate of 2.1 Hz a resistivity change of(R(H)-R(o)) /R(H) > 350% (at T=100 K and H=1.2 T) is observed, at 6 Hz no magnetor esistive effect is found. Scanning tunneling microscopy reveals that f ilm morphology is continuous in the first case, and is characterized b y column-growth in the second case leading to inferior electrical prop erties.