Magnetic properties of crystalline La_(0.7)Ca_(0.3)MnO_(3) films including a nanoscale disordered phase

摘要

The magnetic properties of amorphous, crystalline (with disordered inclusions) and perfectly crystalline La_(0.7)Ca_(0.3)MnO_(3) thin films have been investigated. It was shown that the amorphous film is a paramagnet with the effective magnetic moment of 4.2 μ_(B)/Mn ion. The crystalline film with nanoscale disordered inclusions demonstrates a superposition of the ferromagnetic (corresponding to the crystalline matrix) and the superparamagnetic (corresponding to the nanocrystalline disordered inclusions) contributions in the magnetization. The completely crystalline film undergoes only a ferromagnetic transition.