Scientists at the University of Cambridge have created a teeny-tiny fully functional engine, whose prototype motors is dependant on lasers, gold particles, and the attraction between atoms and molecules commonly referred to as Van Der Waals forces in Physics. This microscopic engine is a fraction of an ant’s size, the fraction being a millionth. Imagining an ant used to be pretty easy, but it’s difficult to figure one reduced to a 100 pieces. Here we’re talking of a million pieces, yes, the engine’s THAT small.

Moving on, here’s how the nanoscale engine works – gold particles are meshed in a liquid polymer gel, which the scientists then hit with laser for a really brief moment. This laser beam heats the gel and expels the water upwards (similar to how you wring a cloth). Without the watery divider, the gold particles attract each other owing to their mutual van der Waals attraction. Once the gel cools down, the polymer soaks up water once again, causing the gold particles to aggressively snap apart. Tao Ding, a researcher at Cambridge’s experimental physics laboratory and an author of the paper, stated that the reaction is something close to an explosion, where hundreds of gold balls fly off in a millionth of a second as water molecules inflate the polymers around them. The researchers are super sure that this constriction-expansion cycle could generate enough power to run a nanomachine.

tiny nanoscale engine

An artist’s rendering of the nano-engine (via: University of Cambridge NanoPhotonics)

Now this kind of an engine would be very efficient given its size. Jeremy Baumberg, a University of Cambridge NanoPhotonics professor and an author of the paper stated that they could generate 10 nano-Newton forces, about ten to hundred times more force per unit weight than any other known functional machine, from jet engines to molecular motors. He called the tiny engine “actuating nano-transducers” – or ANTs in short, just like the small but efficient and strong insects (ants carry load fifty times their own weight).

Though in the past we’ve had many claims to the tiniest engine tag, the Cambridge researchers maintain that their is the first dig at a more functional nano-robot motor, all due to the unique application of van der Waals force, and they believe that this could form the foundations for practical nanoscale engines. The gel they’ve used offers enough power to get the nano-device into our watery bodies. The nanomachines easily swim inside our bodies thanks to abundance of water. Considering the viscosity of water, it’ll require a tremendous force to make practical devices. Also, since the Cambridge nanoscale engine is powered by light, there’s no use for wires.

The main challenge the team is currently facing is harnessing the forces for motion in just one direction. As of now the constriction and expansion scatters the force in all directions.

The team is attempting to find microfluidics bio-applications for the technology, and is closely working with the university’s commercial arm Cambridge Enterprise and other companies to achive its goal. The research has received funding from UK Engineering and Physical Sciences Research Council (EPSRC) and the European Research Council (ERC).