Negative differential resistance and pulsed current induced multi-level   resistivity switching in charge ordered and disordered manganites
  We have investigated direct and pulsed current induced electroresistance in two manganites with different electronic and magnetic ground states: charge-orbital ordered 50 % Ca doped NdMnO3 and 50 % Mn doped LaNiO3. It has been shown that negative differential resistance observed at high current density in these compounds is related to Joule heating. However, bi-level and multi-level resistivity switching induced by variations in pulse width and pulse period at low current density can not be attributable to Joule heating alone. We discuss possible origins. 
A. Rebello and R. Mahendiran