  The manganese induced magnetic, electrical and structural modification in
InMnP epilayers, prepared by Mn ion implantation and pulsed laser annealing,
are investigated in the following work. All samples exhibit clear hysteresis
loops and strong spin polarization at the Fermi level. The degree of
magnetization, the Curie temperature and the spin polarization depend on the Mn
concentration. The bright-field transmission electron micrographs show that InP
samples become almost amorphous after Mn implantation but recrystallize after
pulsed laser annealing. We did not observe an insulator-metal transition in
InMnP up to a Mn concentration of 5 at./%. Instead all InMnP samples show
insulating characteristics up to the lowest measured temperature.
Magneotresistance results obtained at low temperatures support the hopping
conduction mechanism in InMnP. We find that the Mn impurity band remains
detached from the valence band in InMnP up to 5 at./% Mn doping. Our findings
indicate that the local environment of Mn ions in InP is similar to GaMnAs,
GaMnP and InMnAs, however, the electrical properties of these Mn implanted
III-V compounds are different. This is one of the consequences of the different
Mn binding energy in these compounds.
