Modifications of electronic transport behaviour of 250 MeV Ag ion irradiated La0.75Ca0.25MnO3 thin films

The influence of swift heavy ion (SHI) irradiation on electronic transport properties of epitaxial thin films of La0.75Ca0.25MnO3 is studied. The films were irradiated with 250 MeV Ag17+ beam at fluence range 101-1012 ions/cm2. A systematic variation in metal-insulator transition temperature (T p) and peak resistivity have been observed. At low fluence value (3 x 101 ions/cm2) the T p is increased by 34 K. With the increase in fluence it decreases but remain at upper side up to the fluence value of 3 x 1011 ions/cm2 as compared to the unirradiated film. The peak resistivity is also decreasing with the increase in fluence up to 3 x 1011 ions/cm2 and then increases with further increase of fluence. The temperature coefficient resistivity (TCR) is also increased with the fluence. The observed effects are correlated with the effects produced by the applications of hydrostatic pressure. The results are discussed in terms of SHI irradiation induced structural strains in the films