Current-induced electroresistance in Nd0.5Ca0.5Mn0.95Ni0.05O3

TL;DR

This study explores how dc and pulsed currents influence electroresistance in Nd0.5Ca0.5Mn0.95Ni0.05O3, revealing complex behaviors including negative differential resistance and resistivity switching, with implications for understanding Joule heating effects.

Contribution

It demonstrates that pulsed current control can induce resistivity switching in manganite without solely relying on Joule heating effects.

Findings

Negative differential resistance appears above a threshold current.

Resistivity switching can be controlled by pulse width and period.

Joule heating influences high dc current electroresistance but not pulsed nonlinearity.

Abstract

We have investigated the dc and pulsed current-induced electroresistance in phase separated manganite Nd0.5Ca0.5Mn0.95Ni0.05O3 (NCMONi05) as a function of temperature and magnetic field. It is shown that the negative differential resistance which appears above a threshold current (Ic) and hysteresis in the V-I progressively vanish with increasing period of the current pulses. However a strong non-linearity in V-I exists even for a pulse period of 6s. The peak voltage at Ic decreases in magnitude and shifts towards higher current values with increasing strength of the magnetic field. The strong nonlinear behavior and the negative differential resistance in the dc current sweep are accompanied by a rapid increase of the sample surface temperature and therefore primarily arise from the Joule heating in the sample. While the Joule heating assists electroresistance in the high dc current regime, the nonlinearity in the pulsed current sweep and the resistivity switching between a high and low value induced by controlling the width and period of pulses can not be explained solely on the basis of Joule heating.