Resistive switching in La_0.3Ca_0.7MnO₃/YBa₂Cu₃O_7-δ devices

We have deposited La_0.3Ca_0.7MnO₃ (LCMO) /YBa₂Cu₃O_7-δ (YBCO) on SrTiO₃ (STO) (100) oriented substrate by sputtering technique at pure oxygen atmosphere at high pressure (4 mbar) to study the resistive switching response. We grew systematically the insulator LCMO film with different thicknesses (t_LCMO= 60, 30 and 15 nm) on YBCO layer (t_YBCO= 60 nm), which acts as bottom electrode. For the electric characterization, we deposited Ag circles on top of the heterostructures as top electrode. From XRD we found that the LCMO and YBCO layers grew textured aligned with substrate. The electrical properties with temperature measurements indicated the LCMO insulator behavior and the YBCO conduction at room temperature. I versus V curves at room temperature showed hysteretic behavior and the presence of two resistive states, whose electrical transport mechanism could be associated with space charge limited conduction (SCLC). The performed resistance switching with applied voltage tests indicate a dependence of the high resistance state (HRS)/ low resistance state (LRS) ratio with LCMO thicknesses.