Temperature dependence of the domain wall width in LaAlO3

Abstract
Twin wall related diffuse scattering intensities from a single crystal of LaAlO3 were determined using high-resolution x-ray diffraction methods. Rocking curves were measured for sample temperatures between 295 and 900 K. The wall thickness W was determined by comparing the observed diffraction profiles with structure factor calculations for a tanh(x/W) wall profile. It is shown that W≈20 Å at low temperatures and increases slowly with temperature reaching values in excess of 200 Å near Tc≈850 K with W∝|T−Tc|−1.