The current-induced effect on the Jahn–Teller distortion in the La 0.5Ca 0.5MnO 3 manganite

Abstract

The influence of dc current on the resistivity ρ and the Young's modulus E of La 0.5Ca 0.5MnO 3 compound has been investigated by means of an in situ measuring method. At low temperatures, both the resistivity ρ and the relative modulus Δ E increase with the current. A relaxation behavior of ρ to the higher resistive state is observed at a fixed temperature and a constant current. After storing the sample for a few days, ρ decreases with the current, accompanying a slight drop of Δ E at low temperatures. Current-induced effects on ρ and Δ E are interpreted according to the current-induced interwinning of Mn 3+O 6 octahedral distortion modes between Q 2- and Q 3-types, which is suggested to contribute to the variation of the resistivity.