Robust electronic phase separation on nanoscale of perovskite manganite La0.825Sr0.175MnO3

Abstract

Electronic phase separation (EPS) plays a key role in elucidating the effects of complexity on emergent behavior for correlated electronic materials. In this work, we thoroughly studied a robust EPS existed in perovskite manganite La0.825Sr0.175MnO3. Results show that a typical paramagnetic-ferromagnetic (PM-FM) phase transition and a metallic-insulating phase transition occur at 285.4 and 295 K, respectively. Electron paramagnetic resonance (EPR) spectroscopy confirms that there are a double peaks rather than a single peak structures in the temperature region of 290 K≤T≤315 K, indicating that an obvious EPS state generates in this compound. Based on the variation of EPR intensities, we found that the FM composition continues to increase with the decrease of temperature in the whole EPS region. Moreover, it causes a percolative-like metallic-insulting transition when the percolative threshold approach ∼22.63% which is nearly equivalent to 25.34% obtained by calculating the ratio of spontaneous magnetization against theoretical saturated magnetization. Detailed phase diagram shows that the EPS state not only occupies most of PM region but also a state of multiphase coexistence is also found.