  When N driven atoms emit in phase into a high-Q cavity mode, the intracavity
field generated by collective scattering interferes destructively with the pump
driving the atoms. Hence atomic fluorescence is suppressed and cavity loss
becomes the dominant decay channel for the whole ensemble. Microscopically 3D
light-intensity minima are formed in the vicinity of the atoms that prevent
atomic excitation and form a regular lattice. The effect gets more pronounced
for large atom numbers, when the sum of the atomic decay rates exceeds the rate
of cavity losses and one would expect the opposite behaviour. These results
provide new insight into recent experiments on collective atomic dynamics in
cavities.
