  We report the fabrication of Ge:Mn ferromagnetic semiconductors by Mn-ion
implantation into Ge followed by pulsed laser annealing. Benefiting from the
short time annealing, the hole concentration in Mn-implanted Ge has been
increased by two orders of magnitude from 10$^{18}$ to over 10$^{20}$
cm$^{-3}$. Likely due to the high hole concentration, we observe that the
longitudinal and Hall resistances exhibit the same hysteresis as the
magnetization, which is usually considered as a sign of carrier-mediated
ferromagnetism.
