States » South


A multi-national study by researchers that included IIT-Madras faculty shows molecular motion might help control nanoscale electronic devices

Chennai, Oct 23 (UNI) A multi-national study by researchers that included a member of the IIT-Madras faculty, has revelead that molecular motion might help control nanoscale electronic devices.
The international research team has made a breakthrough in fundamental research at the intersection of physics, chemistry and nanotechnology, by focussing on how molecular motion and electrical transport (the movement of electric charge) affect each other. This could help researchers develop nanoscale components whose electrical response can be controlled by molecular motion.
Scientists are studying molecular machines for their potential applications in nanotechnology and molecular electronics. The study shows how electrical current can drive molecular motion and how molecular rotation can, in turn, enhance electrical conduction at the atomic scale, advancing our understanding of molecular machines and their potential role in future nanoscale technologies.
The researchers demonstrated a mechanism in which molecular motion and electrical conduction influence each other at the atomic scale. They showed a molecular machine in which an electric current drives the directional rotation of a single molecule, and this rotation, in turn, can increase electrical current through the molecule.
The research involved collaborators from five countries - India, Israel, Germany, Denmark and China.
Molecular machines are structures that perform specific functions in response to stimuli such as light, chemicals or electricity. Biological systems use molecular machines to perform essential cellular functions. Scientists are studying molecular machines for their potential applications in nanotechnology and molecular electronics.
A major challenge has been to understand how an electrical current can drive controlled molecular motion and how that motion, in turn, changes the electrical current.
The study shows how electrical current can drive molecular motion and how molecular rotation can, in turn, enhance electrical conduction at the atomic scale, advancing our understanding of molecular machines and their potential role in future nanoscale technologies.
The study has been published in Nature, a peer‑reviewed international scientific journal widely regarded as one of the world’s leading research journals. Dr. Anil Kumar Singh from IIT Madras is a corresponding author and the principal experimental contributor to the study.
Dr. Anil Kumar Singh, Assistant Professor in the Atomic-Scale Quantum Devices Laboratory, Department of Physics, said, “An exciting aspect of this work is that molecular motion is not merely a consequence of electrical transport; it can also facilitate the passage of electrons through the molecule. As the molecule rotates, it accesses configurations with higher electrical conductance that are not readily accessible when the molecule is at rest. By demonstrating this feedback between rotation and electrical conduction in a single-molecule junction, we have taken a step towards understanding how mechanical motion and electronic function can be coupled at the atomic scale.”
“This is a fundamental proof-of-principle demonstration, rather than a technology ready for practical use. The experiments were performed at cryogenic temperatures, and further research will be needed to establish reliable operation under practical conditions. Nevertheless, the findings provide a foundation for exploring future molecular-scale switches, current-modulating elements and systems designed to promote directional transport near surfaces. These remain potential applications rather than demonstrated outcomes”, he said.
Inspired by the Archimedean screw, a device traditionally used to lift water that can also operate in reverse as a turbine, the researchers investigated whether a similar relationship between electrical current and rotation could be demonstrated in a single molecule.
The team demonstrated a molecular rotor based on helicene, a molecule with a spiral structure resembling a tiny screw. Using a technique known as a mechanically controllable break junction, the researchers suspended a single helicene molecule between two gold electrodes. When a voltage was applied, the electrical current drove the molecule through a cyclic sequence of configurations.
A distinctive finding was the directionality of this motion. In all 122 cases in which the direction of the transitions could be determined, the researchers observed the same cyclic sequence. Reversing the voltage polarity reversed the sequence, indicating that the direction of molecular rotation could be controlled electrically.
The researchers also observed a sharp increase in electrical current beyond a threshold voltage. Experimental measurements, supported by theoretical calculations, indicated that the molecule transitions from moving stepwise between preferred orientations to continuous rotation. During this rotation, the molecule passes through configurations that allow electrons to flow more readily, increasing the current through the intact molecular junction by up to approximately 100-fold.
The onset of this enhancement could also be tuned by gently stretching or compressing the junction. This changes the effective pitch of the helical molecule and influences the conditions under which rotation occurs.
UNI GV 1335
More News

Water level in Tirumala reservoirs rises by 61,68 lakh gallons

23 Oct 2026 | 11:12 PM

Tirumala, Oct 23 (UNI) In a welcome relief for the hill town, the water levels across the five major drinking water reservoirs in Tirumala witnessed a slight rise registering fresh inflows of 61.68 lakh gallons as of Friday morning.

see more..

Sting Operation: KPCC to issue showcause notice to Kripa Alva

23 Oct 2026 | 11:02 PM

Mysuru, Oct 23 (UNI): Karnataka Pradesh Congress Committee (KPCC) president BK Hariprasad on Friday said the party would issue a showcause notice to its spokesperson Kripa Alva, seeking an explanation over her alleged involvement in the purported sting operation targeting former Chief Minister Siddaramaiah.

see more..

Karnataka HC directs constitution of district panels to tackle illegal immigration

23 Oct 2026 | 10:54 PM

Bengaluru, Oct 23 (UNI) The Karnataka High Court has directed the state government to constitute and operationalise district-level committees to deal with cases of illegal immigration within three months, strictly in accordance with the prescribed standard operating procedure (SOP).

see more..

CBI apprehends 2 Lucknow ED officials in Rs 5 lakh bribery case

23 Oct 2026 | 9:52 PM

Chennai, Oct 23 (UNI) The Central Bureau of Investigation (CBI) on Friday arrested a Enforcement Officer (EO) of Lucknow and its Head Constable (HC) in a Rs five lakh bribery case.

see more..

Kakinada Municipal Commissioner Launches ‘Swachh Kakinada’ Sanitation Drive, Issues Cyclone Alert

23 Oct 2026 | 9:26 PM

Kakinada, Oct 23 (UNI) Municipal Corporation Commissioner N.V.V. Satyanarayana on Friday inaugurated a special sanitation drive across the city, aiming to transform the port town into a garbage-free ‘Swachh Kakinada.’
Emphasizing that community participation is key to the campaign’s success, the Commissioner announced the appointment of designated special officers for every municipal ward to resolve civic grievances on the spot.

see more..