Room temperature electroresistance in Sr2−xGdxMnTiO6 perovskites (0 ≤ x ≤ 1)

We report on the room temperature strong (∼80%) electroresistance (ER) in the double perovskite with mixed Mn valence: Sr2−xGdxMnTiO6, 0 ≤ x ≤ 1. Both, continuous and pulsed current–voltage curves are almost identical which indicates that the observed electroresistance is not associated with heating. This is also supported by simultaneous temperature measurements. ER is negligible (absent) in the x = 0 compound and increases with the increase of Gd content ‘x’. The amplitude of ER has a maximum for x = 0.75, suggesting that ER is determined by both the double exchange and the Mn3+ concentration. At the same time, magnetic interactions change from the antiferromagnetic (x = 0) to ferromagnetic ones as x → 1, thus linking the ER with ferromagnetism.

Research highlights
► Giant room temperature electroresistance in Sr2−xGdxMnTiO6 is reported.
► Electroresistance is not associated with heating, as shownby almost identical continuous and pulsed current–voltage curves and is supported by simultaneous temperature measurements.
► The amplitude of ER has a maximum for x = 0.75, suggesting that ER is determined by both the double exchange and the Mn3+ concentration.
► The magnetic interactions at room temperature shift from AF toward FM coinciding with the appearance of adiabatic ER.