We present photoluminescence (PL) measurements of self-assembled In(Ga)As QRs in strong pulsed magnetic fields. The results show a striking modulation of the intensity. This modulation of the emission can be attributed to an effect predicted by Govorov et al.: a mechanism for the topological phase of a neutral particle, a polarized exciton confined to a semiconductor quantum ring. The magnetic-field induced phase strongly affects the excitons in the QR, resulting in switching between bright exciton ground states and novel dark states.