  We report on the exchange coupling and magnetic properties of a strained
ultrathin CoO/PtFe double-layer with perpendicular magnetic anisotropy. The
cobalt oxide growth by reactive molecular beam epitaxy on a Pt-terminated
PtFe/Pt(001) surface gives rise to an hexagonal surface and a monoclinic
distorted CoO 3nm film at room temperature. This distorted ultrathin CoO layer
couples with the PtFe(001) layer establishing a robust perpendicular exchange
bias shift. Soft x-ray absorption spectroscopy provides a full description of
the spin orientations in the CoO/PtFe doublelayer. The exchange bias shift is
preserved up to the Neel antiferromagnetic ordering temperature of TN=293 K.
This unique example of selfsame value for blocking and ordering temperatures,
yet identical to the bulk ordering temperature, is likely related to the
original strain induced distortion and strengthened interaction between the two
well-ordered spin layers.
