Current-induced phase control in charged-ordered Nd0.5Ca0.5MnO3 and Pr0.6Ca0.4MnO3 crystals

TL;DR

This study investigates how electric current influences phase transitions in Nd0.5Ca0.5MnO3 and Pr0.6Ca0.4MnO3 crystals, revealing current-induced insulator-metal transitions and charge-ordering suppression at low temperatures.

Contribution

It demonstrates that electric current can control phase transitions in these manganite crystals, showing effects comparable to magnetic fields and highlighting the first-order nature of the transition.

Findings

Current induces insulator-metal transition at low temperatures.

Charge-ordering temperature decreases with increasing current.

Thermal hysteresis indicates first-order transition.

Abstract

Single crystals of Nd0.5Ca0.5MnO3 and Pr0.6Ca0.4MnO3 show current-induced insulator-metal transitions at low temperatures. In addition, the charge-ordering transition temperature decreases with increasing current. The electroresistive ratio, defined as r0.5/rI where r0.5 is the resistivity at a current of 0.5 mA and rI the resistivity at a given applied current, I, varies markedly with temperature and the value of I. Thermal hysteresis observed in Nd0.5Ca0.5MnO3 and Pr0.6Ca0.4MnO3 at the insulator-metal transition indicates that the transition is first-order. The current-induced changes are comparable to those induced by magnetic fields, and the insulator-metal transition in Pr0.6Ca0.4MnO3 is accordingly associated with a larger drop in resistivity.