Optical properties of wurtzite InAs/InP core-shell nanowires grown on silicon substrates

InAs/InP core-shell nanowires (NWs) are grown on Si(001) and Si(lll) substrates by catalyst assisted molecular beam epitaxy (MBE). Structural characterization of the core-shell NWs shows that the crystallographic structure is pure wurtzite without any stacking faults and that both axial and radial growth occur simultaneously. The investigation of the optical properties reveals that the core-shell NWs are emitting in the telecommunication bands with a radiative lifetime of 5 ns range at 14K. The room temperature photoluminescence (PL) intensity is equal to 5% of the 14K PL intensity confirming the good quality of the NWs.