  In order to explain the recently observed phenomenon of optical orientation
of a single Mn spin residing inside a quantum dot, a process of Mn spin
relaxation with characteristic timescale of tens of nanoseconds had been
invoked. We show that after taking into account the mixing of states of the
exciton and the Mn spin (due to the sp-d exchange interaction), the observed Mn
optical orientation time can be explained by invoking only the processes of
carrier spin relaxation.
