  We study a quantum information storage scheme based on an atomic ensemble
with near (also exact) three-photon resonance electromagnetically induced
transparency (EIT). Each 4-level-atom is coupled to two classical control
fields and a quantum probe field. Quantum information is adiabatically stored
in the associated dark polariton manifold. An intrinsic non-trivial topological
structure is discovered in our quantum memory implemented through the symmetric
collective atomic excitations with a hidden SU(3) dynamical symmetry. By
adiabatically changing the Rabi frequencies of two classical control fields,
the quantum state can be retrieved up to a non-abelian holonomy and thus
decoded from the final state in a purely geometric way.
