  In 2013 the IceCube collaboration announced the discovery of a cosmic
neutrino flux up to PeV energies, validating neutrino astronomy as the next
promising observational technique to explore the high-energy Universe. The
neutrino community is moving forward with the construction of new facilities to
enhance the detection of these elusive particles at higher energies (up to and
beyond EeV) and to increase the statistics at the high-energy end of the
IceCube neutrino flux. Future large volume neutrino detectors, using both the
radio Askaryan and the optical Cherenkov signal, will open the possibility of
hybrid detection of neutrino interactions within the polar ice. In this
contribution we present a first calculation of the expected number of events
for a simplified geometry of one radio station located at 200 m depth in the
vicinity of a ~10 km^3 in-ice Cherenkov detector, similar to the planned
IceCube-Gen2 neutrino observatory. Preliminary simulations show that a total
event rate of ~1 event/year is achievable for a 10-stations array assuming that
the Askaryan radio detectors can lower their energy threshold down to ~PeV
energies. Such a possibility is currently under study for the future radio
extension foreseen as one of the surface components of IceCube-Gen2.
