No abstract

No abstract

No abstract

No abstract

Polarized Raman spectroscopy has been applied for Bi1∕2Sr1∕2MnO3 thin films on SrTiO3(001) substrate in order to clarify the charge- and orbital-ordering patterns. From the mode assignment on the basis of group theoretical analysis and the lattice dynamical calculations previously reported, it is concluded that the conventional checkerboard charge-order model is more appropriate than the Zener polaron model. It is also confirmed that the major peaks are activated by charge and orbital ordering from the comparison between the temperature dependence of the intensity of the (1120) superlattice reflection peak in synchrotron x-ray powder diffraction and that of the intensity of the phonon peaks observed in the Raman spectra.