Evidence for instability in charge ordering Nd0.5Sr0.5MnO3

The transport properties and magnetic phase transitions of charge ordering manganites Nd0.5Sr0.5MnO3 have been investigated. From resistivity measurements, a continuous increase of resistivity upon the thermal cycling occurs at T≤150K, and shows an instable behavior in the system. The experimental results of magnetization and electron-spin-resonance spectra indicate that the ferromagnetic phase and antiferromagnetic phase coexist in a broad temperature region. We think that the origin of the instability stems from an inhomogeneous strain yielded in the ferromagnetic interface, due to the competition among different phases.