  We investigate the quantum interference effects of single photon transfer in
two-atom cavity system caused by external excitation phase. In the proposed
system, two identical atoms (with different positions in the optical cavity)
are firstly prepared into a timed state by an external single photon field.
During the excitation, the atoms grasp different phases which depend on the
spatial positions of the atoms in the cavity. Due to strong resonant
interaction between two atoms and optical cavity mode the absorbed input photon
can be efficiently transferred from the atoms to the resonant cavity mode. We
show that the quantum transfer is highly sensitive to the external excitation
phases of atoms and it leads to quantum interference effects on the cavity mode
excitation. Besides, the quantum transfer is also influenced by the
dipole-dipole interaction dependent to the atomic distance. In this system the
atomic positions also determine the coupling constants between atoms and cavity
mode which causes additional interference effects to the photon exchange
between atoms and cavity. Based on the characteristics of excitation phase we
find that it is a feasible scheme to generate long-lived dark state and it
could be useful for storage and manipulation of single photon fields by
controlling the excitation phase.
