Photoluminescence polarization and piezoelectric properties of InAs/InP quantum rod-nanowires

Purely wurtzite InAs/InP quantum rod nanowires (QRod-NWs) emitting at 1.55 μm have been successfully grown on silicon substrates by VLS assisted molecular beam epitaxy. Microphotoluminescence studies of single QRod-NWs reveal a highly linearly polarized emission parallel to the nanowires axis. This very high degree of linear polarization (> 0.9) can be explained by the photonic nature of the NW structure. Moreover, these QRod-NWs reveal a broad peak with an asymmetric lineshape at 10K. From experimental and theoretical studies, we conclude that this feature is a consequence of a piezoelectric field induced by the strained InAs QRod.