SU(3) surface tension from the lattice with the fixed point action

The surface tension at the deconfinement transition of SU(3) is determined with a parametrized version of the fixed point action of a renormalization group transformation on lattices with temporal extent Nτ=3 and 4 and spatial extent Nσ/Nτ=3 and 4. A considerable cut-off dependence can be seen in comparison with earlier determinations from tree level Symanzik and tadpole improved actions.