  We show that pure spin injection from a magnetic electrode into an inversion
symmetry-broken system composed of a tunnel barrier and a metallic region
generates a transverse charge current. Such a tunnelling spin galvanic
conversion is robust to disorder and non-local, i.e. injection and detection
contacts do not coincide, and is strongly anisotropic whenever the internal
spin-orbit field has a non-trivial angular dependence. The anisotropy shows up
in linear response, contrary to what happens in bulk conversion setups lacking
tunnelling elements. This is particularly relevant for spin-charge conversion
at oxide interfaces, where both the tunnel barrier and the receiving
low-dimensional metallic system host effective spin-orbit fields with complex
angular symmetries.
