  The atom-photon entanglement is studied in a three-level lambda-type
closed-loop atomic system in multi-photon resonance condition and beyond it. It
is shown that the von Neumann entropy in such a system is phase dependent, and
it can be controlled by either intensity or relative phase of applied fields.
It is demonstrated that for the special case of Rabi frequency of applied
fields, the system is disentangled.
