  We consider an interferometer based on artificially induced topological
superconductivity and chiral 1D Majorana fermions. The (non-topological)
superconducting island inducing the superconducting correlations in the
topological substrate is assumed to be floating. This allows probing the
physics of interfering Majorana modes via microwave response, i.e., the
frequency dependent impedance between the island and the earth. Namely,
charging and discharging of the island is controlled by the time-delayed
interference of chiral Majorana excitations in both normal and Andreev
channels. We argue that microwave measurements provide a direct way to observe
the physics of 1D chiral Majorana modes.
