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The perovskite La_(0.67)Ca_(0.33)MnO_3/La_(0.67)Sr_(0.33)CoO_3/La_(0.67)Ca_(0.33)MnO_3 trilayers were fabricated by a facing-target sputtering technique and their magnetotransport properties were investigated. The magnetoresistance is dependent on spacer thickness and dramatically decreases when La_(0.67)Sr_(0.33)CoO_3 layer is thick enough because of its short-circuiting effect. Different from La_(0.67)Ca_(0.33)MnO_3 single layer, trilayer films with thin La_(0.67)Sr_(0.33)CoO_3 spacer have the enhanced metal-semiconductor transition temperature (T_(MS)) of La_(0.67)Ca_(0.33)MnO_3 layers. The magnetic coercivity H_C shows a nonmonotonic behavior with changing the spacer layer thickness at 230 K. The waist-like hysteresis indicates that there is an indirect exchange coupling between the top and bottom La_(0.67)Ca_(0.33)MnO_3 layers across the spacer La_(0.67)Sr_(0.33)CoO_3 layer.
The perovskite La 0.67 Ca 0.33 MnO 3 / La 0.67 Sr 0.33 CoO 3 / La 0.67 Ca 0.33 MnO 3 trilayers were fabricated by a facing-target sputtering technique and their magnetotransport properties were investigated. The magnetoresistance (0.67) Ca_ (0.33) MnO_3 single layer, trilayer films with thin La_ (0.67) Sr_ (0.33) CoO_3 layer is thick enough because of its short- circuiting effect. The magnetic coercivity H_C shows a nonmonotonic behavior with changing the spacer layer thickness at 230 (0.67) Ca_ (0.33) MnO_3 layers. K. The waist-like hysteresis indicates that there is an indirect exchange coupling between the top and bottom La_ (0.67) Ca_ (0.33) MnO_3 layers across the spacer La_ (0.67) Sr_ (0.33) CoO_3 layer.