Ion implanted In0.53Ga0.47As for ultrafast saturable absorber device at 1.55 μm

Iron (Fe) ion implantation with post-annealing was used to shorten the carrier lifetime of In
0.53
Ga
0.47
As-based saturable absorber due to an effective Fe
³⁺
/Fe
²⁺
trap level. The modulation depth and the nonsaturable loss were investigated. Moreover, we found that the saturation of Fe-related trap level at high excited carrier density can be avoided by introducing Zn dopant in InGaAs. Furthermore, by comparing As and Fe-implanted InGaAs samples, we found that Fe
²⁺
/Fe
³⁺
is more effective as a trap center for electrons and holes, while ionized As is a trap center only for electrons in InGaAs.