Colossal electroresistance and colossal magnetoresistive step in paramagnetic insulating phase of single crystalline bilayered manganite(La$_{0.4}$Pr$_{0.6}$)$_{1.2}$Sr$_{1.8}$Mn$_{2}$O$_{7}$

TL;DR

This study demonstrates a colossal electroresistance and magnetoresistive step in a bilayered manganite's paramagnetic insulating phase, revealing significant resistance changes under electric current and magnetic field, linked to charge-ordered clusters.

Contribution

It reports the first observation of colossal electroresistance and a sharp magnetoresistive step in the PMI phase of a bilayered manganite, highlighting the role of charge-ordered clusters.

Findings

Colossal electroresistance of -95% at low temperatures.

Sharp magnetoresistive step near 5T below 10K.

Disappearance of the step with higher current injection.

Abstract

We report a significant decrease in the low-temperature resistance induced by the application of an electric current on the $ab$-plane in the paramagnetic insulating (PMI) state of (La$_{0.4}$Pr$_{0.6}$)$_{1.2}$Sr$_{1.8}$Mn$_{2}$O$_{7}$. A colossal electroresistance effect attaining -95% is observed at lower temperatures. A colossal magnetoresistive step appears near 5T at low temperatures below 10K, accompanied by an ultrasharp width of the insulator-metal transition. Injection of higher currents to the crystal causes a disappearance of the steplike transition. These findings have a close relationship with the presence of the short-range charge-ordered clusters pinned within the PMI matrix of the crystal studied.