  We propose a novel scheme for distinguishing between the Dirac and Majorana
nature of neutrinos via interaction of a neutrino beam with microwave photons
inside a cavity. We study the effective photon-photon polarization exchange
induced by the photon-neutrino scattering. The quantum field theoretical
studies of such effective picture are presented for both Dirac and Majorana
neutrinos. Our phenomenological analyses show that the difference between Dirac
and Majorana neutrinos can manifest itself in scattering rate of the photons.
To enhance the effect a cavity scheme is employed. An experimental setup based
on microwave cavities is then designed and simulated by finite element method
to measure the scattering rate. Our results suggest that an experiment based on
the current state-of-the-art technology will be able to probe the difference in
about one year. However, it can be done in a few days by enhancing the neutrino
beam flux or implementing with the near future equipments. Therefore, our work
provides the possibility %puts the grounds for solving the long lasting puzzle
of Dirac or Majorana nature of neutrinos.
