Optical indication of metallic clusters in the layered manganites aboveN. N. Loshkareva, E. V. Mostovshchikova, N. I. Solin, Yu. P. Sukhorukov, S. N. Tugushev and S. V. Naumov
The Institute of Metal Physics of UD of the Russian Academy of Sciences 620041, Ekaterinburg, S. Kovalevskoy str. 18, Russia
received 26 July 2006; accepted in final form 3 October 2006
published online 1 November 2006
Optical absorption in the bi-layered manganites (x=0.3 and 0.4) was studied and metallic clusters were revealed in the temperature range in the composition with x=0.4. The existence of metal clusters is considered as the principal cause of magnetoresistance, the tails of magnetization and ferromagnetic correlations, which are observed in this manganite up to temperatures several times exceeding the temperature of 3D magnetic ordering.
75.47.Lx - Manganites.
78.20.-e - Optical properties of bulk materials and thin films.
© EDP Sciences 2006