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arXiv · 2510.24291

Viscous AC current-driven nanomotors

Vladimir U. Nazarov·Tchavdar N. Todorov·E. K. U. Gross
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Abstract

The recent discovery that electrons in nano-scale conductors can act like a highly viscous liquid has triggered a surge of research activities investigating consequences of this surprising fact. Here we demonstrate that the electronic viscosity has an enormous influence on the operation of a prototypical AC-current-driven nano-motor. The design of this prototype consists of a diatomic molecule immersed in an otherwise homogeneous electron liquid which carries an AC current. The motion of the diatomic is determined by a subtle balance between the current-induced forces and electronic friction. By ab-initio time-dependent density-functional simulations we demonstrate that the diatomic performs a continuous rotation provided the amplitude and frequency of the imposed AC current lie within certain islands of stability. Outside these islands the nuclear motion is either chaotic or comes to a stand-still. The proposed design of the nano-motor is the conceptually simplest realization of the idea of an molecular waterwheel sandwiched between conducting leads

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Vladimir U. Nazarov, Tchavdar N. Todorov, E. K. U. Gross. 2025-10-28. Viscous AC current-driven nanomotors. https://doi.org/10.1103/cs2v-f9wy

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