Title: Summary Polarization

Choose the correct statement.

- The polarization of a ferroelectric can only be determined indirectly by measuring the difference between the up (+|P|) and down (-|P|) polarized states. (correct)
- The polarization of a ferroelectric is directly measured using a polarimeter.

- The polarization in a 1D centrosymmetric lattice is not uniquely defined, as it depends on the choice of unit cell. (correct)
- The polarization in a 1D centrosymmetric lattice is uniquely defined, regardless of the choice of unit cell.

- The polarization lattice of a centrosymmetric lattice is centrosymmetric. (correct)
- The polarization lattice of a centrosymmetric lattice is non-centrosymmetric.

- The polarization lattice of a non-centrosymmetric lattice is non-centrosymmetric. (correct)
- The polarization lattice of a non-centrosymmetric lattice is centrosymmetric.

- The polarization quantum corresponds to the spacing between values in the polarization lattice. (correct)
- The polarization quantum takes into account the tunneling effect for systems with a characteristic length below 20 nm.

- In a real material, the polarization is not a linear function of the ionic displacement, because the electron cloud rearranges as the ions are displaced. (correct)
- In a real material, the polarization is a quadratic function of the ionic displacement, because the electron cloud rearranges as the ions are displaced.

- The position of the electron cloud can be determined with a Wannier function. (correct)
- The position of the electron cloud can be determined with a Bloch function.