Scaling behaviour of strontium titanate

The dielectric susceptibility, chi = chi' - i chi ", of nominally pure stro ntium titanate is measured between 4 and 70 K as a function of an external bias field. Static scaling analysis of the susceptibility reveals a very go od scaling behaviour with a quasi-critical exponent a = delta/(delta - 1) = 2.00 +/- 0.02 extracted consistently from two different experiments.