Effect of B-Site Substitution on the Critical Behavior in La_0.7Ca_0.3MnO₃

Abstract

The effect of B-site substitution on the critical behavior has been investigated in Cr-doped manganites La_0.7Ca_0.3Mn_1-xCr_xO₃ (x=0.00, 0.03 and 0.06) by means of the pump-probe method. We have observed that the Cr-doping suppresses the critical behavior of the relaxation time τ. This suppression has been interpreted in terms of a reduced correlation length of the photoinduced charge-ordering fluctuations due to the B-site impurities.