Polarized Photouminescence from Single Wurtzite and Zincblende InP Nanowires*

We use polarized photoluminescence spectroscopy of single InP nanowires to compare the optical properties of vapor-liquid-solid growth of single zincblende (ZB) and wurtzite (W) nanowires. Since ZB and W nanowires have different symmetries and selection rules, their optical properties should also be different. The emission from single W nanowires is observed to be $\sim $80 meV higher than for ZB nanowires. Low temperature polarization measurement shows that ZB nanowires are strongly polarized along the nanowire axis, while the W nanowires are polarized perpendicular to the NW axis. The temperature dependence of the ZB and W NW emissions are compared with a bulk InP epilayer. Apart from the 80meV shift in bandgap, the temperature dependencies are similar.