Nanometer-sized regions of charge ordering and charge melting in La 2/3 Ca 1/3 MnO 3 revealed by electron microdiffraction

Electron microdiffraction study of phase transition in La{sub 2/3}Ca{sub 1/3}MnO{sub 3} revealed temperature-dependent (h+1/2,0,l) diffraction spots. Their intensity peaks at T{sub c}. Quantitative electron diffraction intensity analysis shows that they come from nanometer-sized domains with modulated transverse atomic displacements in the orthorhombic a-c plane, which has two types of Mn ions and thus charge ordering. The average domain is {approx}3.6 nm in diameter and {approx}1.5 nm in height (along the b axis). The number of domains increases and then decreases, as the sample is cooled through T{sub c}.