Structure, magnetic properties and phase separation of Nd0.5Ca0.5Mn1−xGaxO3 (0x0.1)

Abstract Structure and magnetic properties of Nd 0.5 Ca 0.5 Mn 1− x Ga x O 3 (0⩽ x ⩽0.1) were investigated systematically through X-ray diffraction, magnetization and electron spin resonance (ESR) measurements. It was found that substituting Mn with Ga reduces the charge ordering temperature ( T CO ) and induces an additional peak in magnetization–temperature curve at low temperature. Both the temperature and magnetic field dependence of the magnetization in zero-field-cooling and field-cooling modes suggest that, in the Ga-doped samples, spin-glass-like phase induced by Ga-doping and antiferromagnetic charge-orbital-ordered (COO) phase coexist at low temperature. Furthermore, the ESR spectra indicate that, when the temperature is between the Neel temperature T N and the T CO , the paramagnetic phase and antiferromagnetic COO phase coexist and the volume fraction of the former increases with temperature at the expense of the latter. In addition, magnetization evidences for the interaction between Nd and Mn ions are present.