Magnetoresistive properties of nanocomposites p-La0,78Mn0,99O3,5 i p-La0,80Mn1,04O3,5 and p-La0,80Mn1,04O3,5 in the temperature range 4.2-300 K and magnetic fields up to 140 kOe

A study is made of the magnetoresistive properties and structure of nanocomposite manganites La0.78Mn0.99O3.5 and La0.80Mn1.04O3.5 formed at different temperatures and durations of the high-pressure sintering. The structural features of the samples are established by x-ray structure and x-ray phase analyses and scanning atomic-force microscopy. The temperature and field dependences of the resistivity of nanostructure LaMnO manganites are obtained. These and other experimental results indicate that the magnetoresistive properties of nanomanganites are influenced materially by phase separation and frozen spin clusters; since those properties depend strongly on the preparation technology, it should be possible to create nanomaterials with specified properties