Abstract
Melting of the charge-ordered state in (La,Ca)MnO3 and (Pr,Ca)MnO3 is characterized by an anomalously large decrease of the wave vector-as much as 25% through the transition. High resolution lattice images obtained from electron microscopy reveal that the large change occurs as a result of formation of new clusters with charge-ordering modulation wavelength increased by integral lattice parameter. Our findings can be attributed to the discrete nature of the charge ordering on the manganese sites.