  We report on a combined experimental and theoretical investigation into the
normal modes of an all-fiber coupled cavity-quantum-electrodynamics system. The
interaction between atomic ensembles and photons in the same cavities, and that
between the photons in these cavities and the photons in the fiber connecting
these cavities, generates five non-degenerate normal modes. We demonstrate our
ability to excite each normal mode individually. We study particularly the
`cavity dark mode', in which the two cavities coupled directly to the atoms do
not exhibit photonic excitation. Through the observation of this mode, we
demonstrate remote excitation and nonlocal saturation of atoms.

Quantum Physics