  Among the potential applications of topological insulators, we investigate
theoretically the effect of coexistence of proximity-induced ferromagnetism and
superconductivity on the surface states of 3-dimensional topological insulator,
where the superconducting electron-hole excitations can be significantly
affected by the magnetization of ferromagnetic order. We find that, Majorana
mode energy, as a verified feature of TI F/S structure, along the interface
sensitively depends on the magnitude of magnetization $m_{zfs}$ in FS region,
while its slope in perpendicular incidence presents steep and no change. Since
the superconducting gap is renormalized by a factor $\eta(m_{zfs})$, hence
Andreev reflection is more or less suppressed, and, in particular, resulting
subgap tunneling conductance is more sensitive to the magnitude of
magnetizations in FS and F regions. Furthermore, an interesting scenario
happens at the antiparallel configuration of magnetizations $m_{zf}$ and
$m_{zfs}$ resulting in magnetoresistance in N/F/FS junction, which can be
controlled and decreased by tuning the magnetization magnitude in FS region.
