  The Dzyaloshinskii-Moriya interaction (DMI) has been shown to stabilise
Ne\'{e}l domain walls in magnetic thin films, allowing high domain wall
velocities driven by spin current effects. DMI occurs at the interface between
ferromagnetic and heavy metal layers with strong spin-orbit coupling, but
details of the interaction remain to be understood and the role of proximity
induced magnetism (PIM) in the heavy metal is unknown. We report interfacial
DMI and PIM in Pt determined as a function of Au and Ir spacer layers in
Pt/Co/Au,Ir/Pt. The length-scale for both interactions is sensitive to
sub-nanometre changes in the spacer thickness, and they correlate over sub
mono-layer spacer thicknesses, but not for thicker spacers. The spacer layer
thickness dependence of the Pt PIM for both Au and Ir shows a rapid monotonic
decay, while the DMI changes rapidly but has a two-step approach to saturation
and continues to change, even after the PIM is lost.
