Wurtzite/Zinc-Blende 'K'-shape InAs Nanowires with Embedded Two-Dimensional Wurtzite Plates

The prediction that Majorana Fermions obey nonabelian exchange statistics can only be tested by interchanging such carriers in "Y'- or 'X'- (or 'K'-) shaped nanowire networks. Here we report the molecular beam epitaxy (MBE) growth of 'K'-shaped InAs nanowires consisting of two interconnected wurtzite wires with an additional zinc-blende wire in between. Moreover, occasionally, the growth results in formation of a purely wurtzite two-dimensional plate between the zinc-blende nanowire and one (sometimes both) intersecting wurtzite arm. By modeling the crystal structure we explain the transformation from wurtzite to zinc-blende and the coexistence of both crystallographic phases in such nanowire structures. To the best of our knowledge neither the MBE growth of an InAs nano-object showing combination of wurtzite and zinc-blende crystal structures nor the growth of pure wurtzite InAs nanoplates in this geometry has been reported before.