  We report on the selective creation of spin filltering regions in
non-magnetic InGaAs layers by implantation of Ga ions by Focused Ion Beam. We
demonstrate by photoluminescence spectroscopy that spin dependent recombination
(SDR) ratios as high as 240% can be achieved in the implanted areas. The
optimum implantation conditions for the most efficient SDR is determined by the
systematic analysis of different ion doses spanning four orders of magnitude.
The application of a weak external magnetic field leads to a sizeable
enhancement of the SDR ratio from the spin polarization of the nuclei
surrounding the polarized implanted paramagnetic defects.
