Microstructure of charge ordered phase and field dependence of charge ordering transition temperature in Pr0.55Ca0.45MnO3

We have made crystallographic analysis for the microstructure of charge ordered phase formed by a charge ordering transition in a Pr0.55Ca0.45MnO3 single crystal, whose structure change is from pseudocubic (high-temperature phase) to pseudotetragonal structure (charge ordered phase). It has been found that the charge ordered phase is composed of many crystallographic domains with {1 0 1}CO (CO represents a charge ordered phase) twinning planes, which correspond to {1 0 1}h (h represents a high temperature phase) planes of pseudocubic structure. In addition, we have examined the magnetic field dependence of charge ordering transition temperature and found that the experimental dependence is in good agreement with the calculated one based on the Clausius-Clapeyron equation