2010 Volume 45 Issue 3 Pages 161-165
The nucleation and growth mechanism of the ferromagnetic phase inside the charge ordered insulator state of La0.25Pr0.375Ca0.375MnO3, which is a typical manganite showing colossal magnetoresistance, was studied by electron holography and Lorentz microscopy. Cryogenic Lorentz microscopy observations revealed a zig-zag interface that separated the ferromagnetic phase from the non-magnetic mother phase. The results indicated a significant pinning effect for the motion of phase boundary, and the pinning forces originated from the structural antipathy between the ferromagnetic phase and the charge-ordered state. We also determined magnetic parameters, such as the magnetocrystalline anisotropy constant, by using the electron microscopy observations.