  The ability to manipulate individual atoms and molecules using a scanning
tunnelling microscope (STM) has been crucial for the development of a vast
array of atomic scale devices and structures ranging from nanoscale motors and
switches to quantum corrals. Molecular motors in particular have attracted
considerable attention in view of their potential for assembly into complex
nanoscale machines. Whereas the manipulated atoms or molecules are usually on
top of a substrate, motors embedded in a lattice can be very beneficial for
bottom-up construction, and may additionally be used to probe the in uence of
the lattice on the electronic properties of the host material. Here, we present
the discovery of controlled manipulation of a rotor in Fe doped
Bi$_{2}$Se$_{3}$. We find that the current into the rotor, which can be finely
tuned with the voltage, drives omni-directional switching between three
equivalent orientations, each of which can be frozen in at small bias voltage.
Using current fluctuation measurements at 1MHz and model simulations, we
estimate that switching rates of hundreds of kHz for sub-nA currents are
achieved.
