  A supersymmetric relativistic quantum theory in the temporal domain is
developed for bi-spinor fields satisfying the Dirac equation. The simplest
time-domain supersymmetric theory can be postulated for fields with
time-dependent mass, showing an equivalence with the bosonic supersymmetric
theory in time-domain. Solutions are presented and they are used to produce
probability oscillations between mass states. As an application of this idea,
we study the two-neutrino oscillation problem, showing that flavour state
oscillations may emerge from the supersymmetry originated by the
time-dependence of the unique mass of the neutrino.
