Current-induced effects in La5/8-yPryCa3/8MnO3 ((y)=0.35) single crystals

摘要

DC electrical current-dependent resistance and pulsed current-voltage characteristics as a function of temperature of mixed valent Mn oxide-based La5/8-yPryCa0.375MnO3 (y = 0.35) single crystals are reported. We find that the low-temperature regime of this material is strongly current dependent. For small current densities (similar to10 muA/cm(2)), the metal-insulator transition related to the low-temperature enlargement of the ferromagnetic fraction is not observed down to 10 K. Higher current densities causes a large decrease of the resistance, which is temperature dependent and exhibits memory effects. Our results are interpreted within a scenario of strong competition between charge and ferromagnetic ordering. (C) 2004 Published by Elsevier B.V.