Temperature dependence of the domain wall width in LaAlO3

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 approximate to 20 Angstrom at low temperatures and increases slowly with temperature reaching values in excess of 200 Angstrom near T(c)approximate to 850 K with W proportional to\T-T-c\(-1). (C) 1999 American Institute of Physics. [S0021-8979(99)01002-6].