Correlation between Electroresistance and Magnetoresistance in Slight Oxygen-Deficient Nd_0.67Sr_0.33MnO_3-δ Polycrystalline Ceramics

A colossal electroresistance effect is found in Nd_0.67Sr_0.33MnO_3-δ polycrystalline ceramics with a very slight oxygen deficiency δ = 0.05. The electroresistance behaviour of Nd_0.67Sr_0.33MnO3-δ(δ= 0.0 ) displays the striking similarity to its counterpart magnetoresistance. It reveals that the boundary effect plays an important role in electroresistance and the same physical origin is likely responsible for both magnetoresistance and electroresistance effects in Nd_0.67Sr_0.33MnO_3-δ polycrystals.