  Based on computer simulations and theoretical analysis, a new dynamic state
is found in inductively coupled intrinsic Josephson junctions in the absence of
an external magnetic field. In this state, the plasma oscillation is uniform
along the c axis and there are $(2m+1)\pi$ phase kinks, with $m$ being an
integer, periodic and thus non-uniform in the $c$ direction. In the IV
characteristics, the state manifests itself as current steps occurring at all
cavity modes. Inside the current steps, the plasma oscillation becomes strong,
which generates several harmonics in frequency spectra at a given voltage. The
recent experiments on terahertz radiations from the mesa of a BSCCO single
crystal can be explained in terms of this state.
