Synchronized motion of noncontact rack-and-pinion devices subject to thermal noise

We study a submicron device composed of one rack and N pinions. The pinions are coupled via the torsional springs. The rack and pinions have no contact, but are intermeshed via the lateral Casimir force. We show that even extremely soft torsional springs allow synchronized motion of N pinions. The total load that the machine lifts up, increases almost linearly with N. The synchronized state blooms even if the spring constants and the distances between the rack and the pinions are not tuned, and the thermal noise looms. These results lead one to be optimistic about harnessing the Casimir force at the nanoscale and the realization of a new generation of nanodevices.