No abstract

No abstract

Electrical resistivity and magnetoresistance measurements on (La0.5Pr0.2)Ba0.3MnO3 thin films of 50 and 200nm thicknesses, irradiated by 200MeV Ag+15 ions, have been carried out. Before irradiation, all the films exhibit insulator-metal transition at a temperature (Tp) of ∼200K. After irradiation, both resistivity and Tp remain mostly unaffected in 50nm thin film but vary largely in 200nm thin films. This disparity in irradiation effect on these films is explained to arise from the interplay of columnar defect induced (i) enhancement in resistivity with increasing thickness of the film and (ii) local release of strain at the interfaces of low thickness films, which decreases resistivity.

No abstract

The thickness dependent current-voltage (I-V) properties of the bilayered La0.6Pr0.2Sr0.2MnO3 (LPSMO)∕Nb-SrTiO3 (SNTO) p-n junction devices having two different thicknesses, grown using pulsed laser deposition (PLD) technique, have been studied. The I-V curves of these bilayered junctions show good rectifying behavior and also exhibit large positive magnetoresistance (MR) at room temperature. The p-n junction having LPSMO thickness of 200nm exhibits low saturation voltage (VC) and high positive MR as compared to junction with 100nm p-type LPSMO layer. Distinct feature such as large positive MR with respect to temperature can be understood in terms of thickness dependent modifications in the film-substrate interface.