Structural, electronic, and polarization properties of Bi_2ZnTiO_6 supercell from first-principles

摘要

First principles calculations were used to investigate the lattice dynamics, electronic property, and spontaneous polarization of Bi_2ZnTiO_6 10-atom supercell. We explore the ground structure from the highest P4/mmm phase by successively freezing in the unstable polar modes. We find that the ground structure is in the Cm symmetry instead of the PAmm symmetry, and the spontaneous polarization is not as large as that of previous belief. Finally, we suggest possible routes by which the energy of metastable PAmm phase may be close to the Cm ground phase to enable a practical realization for polarization rotation.