Transport and magnetic properties of bulk and epitaxial thin film of Pr0.5Sr0.5MnO3

A thin film of Pr0.5Sr0.5MnO3. was prepared by laser ablation technique. The film (2500 Angstrom) shows a ferromagnetic (FM) ordering at 250 K for 200 G field followed by a second transition into an antiferromagnetic (AF) state around 150 K. By applying external fields, T-C shifts to higher temperatures and the magnetisation maximum at T-N shifts to slightly lower temperatures. The onset of the AT behavior in all fields up to 5 T is accompanied by a splitting of the cooling and the warming magnetisation data. The M(T) curve of the bulk sample shows a temperature hysteresis indicating a first order transition. The thermopower (TEP) of the bulk sample remains negative in the temperature range of 77-300 K. We studied the piezoresistance effect of the film under quasi hydrostatic pressure up to 4 kbar. The specific heat data of the bulk sample also indicates FM and AFM transitions by showing small peaks at the respective temperatures. (C) 2001 Elsevier Science B.V. All rights reserved.