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تسجيل مستخدم جديدColossal 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$_{7}$
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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.
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e report the effect of pressure on the steplike magnetostriction of single crystalline bilayered manganite (LaPr)1.2Sr1.8Mn2O8, for our understandings of the ultrasharp nature of the field-induced first-order transition from a paramagnetic insulator
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