Discovery of giant volume magnetostriction at room temperature in La _{1-x} Ba _{x} MnO _{3} manganites

Giant volume magnetostriction ω is found in La _{1-x} Ba _{x} MnO _{3} manganites attained of 4 × 10 ^{-4} in a magnetic field H=8.2 kOe near Curie point T_{C} . In La _{0.7} Ba _{0.3} MnO _{3} ω achieves of giant value of 2.54 × 10 ^{-4} at temperature T=300 K. Volume magnetostriction and magnetoresistance exhibit similar dependence on T and H in T_{C} – region that is explained by the presence in these single crystals of magnetic two-phase ferromagnetic – antiferromagnetic state due to strong s-d exchange.