  To develop active materials that can efficiently respond to external stimuli
with designed mechanical motions is one of the major obstacles that have
hindered the realization of nanomachines and nanorobots. Here, we propose an
innovative working mechanism that allows multifold-translational-motion control
of semiconductor micro/nanomotors by AC dielectrophoresis with simple
visible-light stimulation. We study the dielectrophoresis forces on
semiconducting particles of various geometries in aqueous suspension by
modeling with the consideration of both the Maxwell-Wagner relaxation and
electrical-double-layer-charging effect. With the obtained understanding, we
rationally design a manipulation system that can versatilely transport
semiconductor micro/nanomotors and orient them towards desired directions at
the same time by tuning the light intensity in an electric field. This research
may guide the development of a new type of micro/nanomachine platform with high
versatility and control. It is relevant to nanorobotics and nanodevice
assembly.
