Researchers from multiple institutions have successfully developed a molecular-scale motor based on the Archimedes screw principle, representing a significant advancement in miniaturization technology. The motor consists of a spiral-shaped molecule positioned between two gold electrodes sharpened to atomic dimensions. When electrical voltage is applied, electrons traveling through the spiral molecule transfer angular momentum, causing it to rotate in a controllable manner. The direction of rotation can be reversed by changing the voltage’s polarity.
The research involved collaboration between Prof. Michael Pittelkow’s group at the University of Copenhagen, who designed the spiral molecule, and researchers at the Weizmann Institute of Science in Israel led by Prof. Oren Tal and Dr. Anil Kumar Singh, who conducted the experimental measurements. The team demonstrated that the molecule’s rotation can be precisely controlled by adjusting the separation between the gold electrodes.
A particularly notable discovery emerged during theoretical analysis conducted by Prof. Fabian Pauly’s team at the University of Augsburg using quantum mechanical simulations. The stationary molecule conducted electricity far less efficiently than the rotating molecule, with conductivity increasing by as much as 100 times during rotation. Calculations revealed that the molecular positions most favorable for conducting electricity are actually positions the molecule avoids when at rest; rotation makes these highly conductive arrangements accessible.
This finding indicates that molecular motion influences electrical current flow in unexpected ways, creating a feedback mechanism where rotation enhances electrical conductivity. The research combined experimental measurements with theoretical calculations to fully understand the underlying mechanism, with additional contributions from theoretical physicists at the Niels Bohr Institute in Copenhagen and Huazhong University of Science and Technology in Wuhan.
The achievement opens new possibilities for molecular electronics, spintronics applications, and microfluidic systems. More broadly, the motor demonstrates a new operating principle for designing machines at atomic scales, where electric current generates directed rotation that simultaneously controls the current itself.
Article Attribution | Read More at Article Source
Article summary produced by Claude AI