  We use millimeter wave radiation to manipulate the populations of the energy
levels of a single crystal molecular magnet Fe8. When a continuous wave
radiation is in resonance with the transitions from the ground state to the
first excited state, the equilibrium magnetization exhibits a dip. The position
of this dip varies linearly with the radiation frequency. Our results provide a
lower bound of 0.17 ns for transverse relaxation time and suggest the
possibility that single-molecule magnets might be utilized for quantum
computation.
