Optical probe of ferroelectric order in bulk and thin film perovskite titanates

M. Rössle, C. N. Wang, P. Marsik +8

We have measured the temperature dependence of the direct band gap, $E_g$, in SrTi${}^{16}$O${}_3$ and BaTiO${}_3$ and related materials with quantum-paraelectric and ferroelectric prope…