Reversible switching of InP nanowire growth direction by catalyst engineering

We demonstrate high yield vapor–liquid–solid (VLS) growth of 100-oriented InP nanowire arrays. The highest yield (97%) is obtained when the catalyst droplet is filled with indium prior to nanowire nucleation to the equilibrium composition during nanowire growth. Using these 100 wires as a template we can reversibly switch between a 100 and a 111 growth direction by varying the indium content of the droplet. Modeling VLS growth by a kinetic nucleation model indicates that the growth direction is governed by the liquid–vapor interface energy that is strongly affected by the indium concentration in the catalyst droplet