Resistive characteristics of LSMO/LCMO bi-layers and temperature switching effect of magnetoresistance

Ferromagnetic La0.7Sr0.3MnO3/La0.7Ca0.3MnO3 (LSMO/LCMO) bi-layers of submicron thickness were deposited by magnetron sputtering on SrTiO3 (STO) and Al2O3 (ALO) substrates and temperature dependence of their resistances were investigated. The samples grown on ALO substrates demonstrated lower metal–insulator transition temperatures and higher resistances. The maximum magnetoresistance (MR) of bi-layer grown on STO substrate reached -56% at 184.6 K and magnetic field of 1 T. At temperatures below 150 K a "switching" of MR from negative to positive values (+ 1.7% at 110 K) and a hysteretic behavior of the resistance at low magnetic fields were observed as well.