PREVIEW

Physicists at a UK university have created what they believe could be “the world’s smallest violin” - a microscopic replica so tiny it fits within the width of a single human hair.

Crafted from platinum and measuring just 35 microns long by 13 microns wide (a micron being one-millionth of a metre), the tiny instrument is a feat of precision engineering. For comparison, the diameter of a human hair ranges from 17 to 180 microns, and even tardigrades - the famously tough micro-animals - tend to measure between 50 to 1,200 microns.

But while the violin is not playable, and hasn’t been officially confirmed as a world record-holder, it was never intended to be more than a proof of concept.

The project was designed to showcase the capabilities of Loughborough University’s new nanolithography system - a sophisticated suite of equipment that allows scientists to build, manipulate and analyse materials at the nanoscale. The goal? To pave the way for breakthroughs in computing and energy technologies.

“Though creating the world’s smallest violin may seem like fun and games, a lot of what we’ve learned in the process has actually laid the groundwork for the research we’re now undertaking,” said Professor Kelly Morrison, Head of the Physics department.

“Our nanolithography system allows us to design experiments that probe materials in different ways – using light, magnetism, or electricity – and observe their responses. Once we understand how materials behave, we can start applying that knowledge to develop new technologies, whether it's improving computing efficiency or finding new ways to harvest energy.

“But first, we need to understand the fundamental science and this system enables us to do just that.”

The decision to make a violin was a light-hearted reference to the well-worn phrase, “Can you hear the world’s smallest violin playing just for you?” - a sarcastic response to exaggerated complaints. Often accompanied by a tiny miming gesture, the expression has been popularised in everything from *M*A*S*H* to *pongeBob SquarePants.

The nanolithography system spans an entire laboratory and is centred around the NanoFrazor - a state-of-the-art nano-sculpting machine from Heidelberg Instruments. It works using thermal scanning probe lithography, in which a heated, needle-like tip carves out nanoscale patterns with extraordinary precision.

To create the violin, Professor Morrison, with support from Dr Naëmi Leo and Dr Arthur Coveney, began by coating a small chip in two layers of resist, a gel-like material. The pattern was then burnt into the top layer using the NanoFrazor’s heated tip. After development, a violin-shaped cavity remained, which was then coated with a fine layer of platinum. A final rinse in acetone revealed the finished design.

The whole process takes about three hours, although perfecting the technique took months of testing. The resulting figure is no bigger than a speck of dust and can only be seen in detail under a microscope.

To protect such sensitive work, the equipment is housed in a fully enclosed glovebox with interconnected chambers to guard against moisture and dust. The chip itself is moved between sections using mechanical arms operated from outside the sealed environment.

The system is already powering two significant research projects at Loughborough - one examining alternatives to magnetic data storage, and another exploring the use of heat for faster, more energy-efficient data processing.

“I’m really excited about the level of control and possibilities we have with the set-up,” said Professor Morrison. “I’m looking forward to seeing what I can achieve - but also what everyone else can do with the system.”