Scientists figured out how to use the 'spin' of a single electron to physically crank a microscopic carbon engine.
arXiv · March 16, 2026 · 2603.12723
Why it matters
By passing electricity through a suspended carbon nanotube, researchers can transfer quantum angular momentum directly from individual electrons into mechanical rotation. This allows for the creation of tiny motors driven entirely by the internal magnetic orientation of the flowing current.
From the abstract
We theoretically investigate the current-induced excitation of torsional vibrations in a suspended carbon nanotube (CNT) quantum dot. By considering a CNT clamped between half-metallic ferromagnetic electrodes with an antiparallel magnetization configuration, we demonstrate that the spin-rotation coupling enables the transfer of angular momentum from electron spins to the mechanical torsional mode under a constant source-drain voltage. Using a master-equation approach to analyze the coupled dyna