Phase-coherent transport and spin-orbit coupling in InN nanowires connected in parallel

Semiconductor nanowires based on InN are interesting candidates for future nanolelectronic devices because the surface accumulation layer guarantees a highly conductive channel. However, the spin-transport properties are basically unknown for this material system. In order to obtain information regarding the spin transport, we investigated the low-temperature magnetoconductance of InN nanowires connected in parallel. Usually, phase-coherent transport in small conductors results in conductance fluctuations. By connecting N nanowires in parallel a considerable decrease of the fluctuation amplitude and a reduction of the variance proportional to √(N) can be achieved. This suppression of the fluctuations permits to study weak localization and weak antilocalization effects which are manifested in negative and positive magnetoconductivity around zero magnetic fields, respectively. From these features, information about the phase-coherence length and the spin-orbit scattering length can be obtained. At low magnetic fields we found a clear signature of the weak antilocalization effect indicating the presence of spin-orbit coupling in InN nanowires.