Structure and properties of La–Ca–Mn–O composites prepared by the glass-ceramic method

Synthesis and properties of nanograined La-Ca-manganite–Ni-ferrite composites

“…The magnitude of MR which depends on the magnitude of external magnetic field applied becomes colossal only in the presence of large fields at the transition temperature which inturn depends on the composition. Hence in order to enhance the magnitude of MR in the presence of relatively low fields and at high temperatures, substitution doping [2][3][4][5], grain size reduction [6,7], distribution of the manganite grains in a non-magnetic insulating matrix and magnetic insulating matrix are used as alternative approaches [8][9][10][11][12]. The paramagnetic, semiconducting state to ferromagnetic, metallic state transition temperatures are found to decrease with substitution doping and grain size reduction.…”