Giant volume magnetostriction and colossal magnetoresistance at room temperature inLa0.7Ba0.3MnO3

Abstract

Giant volume magnetostriction at room temperature is found for the first time in aLa0.7Ba0.3MnO3 single crystal,achieving 2.54 × 10−4 in a magnetic field of 8.2 kOe. An even greater value of the volume magnetostriction, equal to4 × 10−4 in the same magnetic field, is observed at the Curie pointTC = 310 K.Volumemagnetostriction and magnetoresistance exhibit similar dependences on temperature and magnetic fieldin the TC-region, that is explained by the presence in this compound of a magnetic two-phaseferromagnetic–antiferromagnetic state due to strong s–d exchange.