Coated conductors have a substrate, a high temperature superconductor layer and at least one or more buffer layers, wherein at least one of the buffer layers is a template for biaxially orienting the high temperature superconductor layer wherein the template is composed of a polycrystalline film consisting of a non-stoichiometric material having the nominal chemical formula A2−xB2+xO7 with B being at least one selected from Zr, Hf, Sn, Pb and Ti; A being at least one selected from La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Y, Tm, Yb and Lu; and x≠0; and wherein the substrate is textured.