La1−xSrxFeO3 solid solutions in magnetic field

Magnetic properties of La1-xSrxFeO3 (x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5) have been investigated in a wide magnetic field range from 0 to 35 T using pulsed high magnetic field magnetization and electron spin resonance measurements. Experimental results show that both the non-magnetic Sr2+ dopant and high magnetic fields affect the stability of the robust antiferromagnetic coupling between Fe ions and induce new phase transitions. Especially the phase transition temperatures and hysteresis behavior show a high sensitivity on the Sr dopant and its doping level. On the other hand, a nonlinear Sr doping level dependence of the transition temperatures and hysteresis behavior were observed, indicating that the charge disproportionation is not the sole influence. Thus, in the series Sr doping La1-xSrxFeO3 samples, the dopant induced FeO6 octahedron distortion and charge disproportionation are coexistence and competition, which leads to a complicated and Sr doping level nonlinearly dependent magnetization behavior.