  Many types of molecular motors have been proposed and synthesized in recent
years, displaying different kinds of motion, and fueled by different driving
forces such as light, heat, or chemical reactions. We propose a new type of
molecular motor based on electric field actuation and electric current
detection of the rotational motion of a molecular dipole embedded in a
three-terminal single-molecule device. The key aspect of this all-electronic
design is the conjugated backbone of the molecule, which simultaneously
provides the potential landscape of the rotor orientation and a real-time
measure of that orientation through the modulation of the conductivity. Using
quantum chemistry calculations, we show that this approach provides full
control over the speed and continuity of motion, thereby combining electrical
and mechanical control at the molecular level over a wide range of
temperatures. Moreover, chemistry can be used to change all key parameters of
the device, enabling a variety of new experiments on molecular motors.
