Current-Induced Resistive Effect in Cu/MgO/La_0.9Sr_0.1 MnO₃ Trilayers on SrTiO₃ (001) Substrates

Cu/MgO/La_0.9Sr_0.1MnO₃ pillars are fabricated on SrTiO₃ (001) substrates by the micro-fabrication patterning processes. Their electric transport properties have been measured in the temperature range from the temperature smaller than the Curie one to 300K. At 125K there emerges abrupt breaks of output voltage in voltage--current (V--I) curves, corresponding to switching in resistance to metastable states, and finally two closed loops are formed with double threshold biases. Around room temperature the V--I characteristics are non-ohmic and show some gradual hysteresis when sweeping the current in a round-trip scan. A large current-induced resistive change ΔR/R₀, ～ -63.2%, is obtained under a current density of 1.0×10⁴ Acm^-2. Especially, ΔR₀depends linearly on the applied current and is independent of the applied magnetic field. The current-induced resistive effect should be of interest for various applications such as switching and field effect devices.