  We demonstrate optically stable amorphous silicon nanowires with both high
nonlinear figure of merit (FOM) of ~5 and high nonlinearity Re({\gamma}) =
1200W-1m-1. We observe no degradation in these parameters over the entire
course of our experiments including systematic study under operation at 2 W
coupled peak power (i.e. ~2GW/cm2) over timescales of at least an hour.
