  We propose a simplified version of the inverse seesaw model, in which only
two pairs of the gauge-singlet neutrinos are introduced, to interpret the
observed neutrino mass hierarchy and lepton flavor mixing at or below the TeV
scale. This minimal inverse seesaw scenario (MISS) is technically natural and
experimentally testable. In particular, we show that the effective parameters
describing the non-unitary neutrino mixing matrix are strongly correlated in
the MISS, and thus, their upper bounds can be constrained by current
experimental data in a more restrictive way. The Jarlskog invariants of
non-unitary CP violation are calculated, and the discovery potential of such
new CP-violating effects in the near detector of a neutrino factory is
discussed.
