  We investigate the effects of Majorana bound states on the ac response of a
quantum resistor-capacitor circuit which is composed of a topological
superconducting wire whose two ends are tunnel-coupled to a lead and a spinless
quantum dot, respectively. The Majorana states formed at the two ends of the
wire are found to suppress completely or enhance greatly the dissipation,
depending on the strength of the overlap between two Majorana modes and/or the
dot level. We compare the relaxation resistance and the quantum capacitance of
the system with those of non-Majorana counterparts to find that the effects of
the Majorana state on the ac response are genuine and cannot be reproduced in
ordinary fermonic systems.
