Australian researchers have developed a microscope that can image tiny biological structures that were previously not visible in what has been described as a significant step for quantum technology.
It is believed to be the first time that quantum technology has improved on existing light microscopes, which in future may lead to improvements in medical imaging and navigation systems.
Quantum technologies are based on the principles of quantum physics, used to describe how tiny systems like atoms and subatomic particles behave.
The quantum microscope works with 35% more clarity – at the scale of bonds between atoms in a cell – than existing state-of-the-art imaging techniques.
Though still an early proof of concept, it is hoped to eventually have wide-ranging applications, including improving MRI scans, and studying nerve degeneration and the effects of antibiotics.
Lead researcher Prof Warwick Bowen, from the University of Queensland, said the quantum microscope outperformed conventional technologies.
“We’ve shown it’s possible to go beyond the limits of classical physics, to see things you could not see in a regular microscope,” he said.
A common problem in imaging tiny structures is the ratio of the signal given off by the thing researchers are trying to look at compared with random light fluctuations in the background of an image.
Scientists had previously overcome this issue by increasing the intensity of a microscope’s light source, using lasers billions of times brighter than the sun – including in techniques that won the Nobel prize for chemistry in 2014.
This can cause problems in the biological samples being studied, said Prof Brant Gibson at RMIT, who was not involved in the study.
“They get killed, they change their behaviour,” said Bowen. “All sorts of stuff happens that makes it really difficult to interpret what is going on in biological systems.”
To get a clearer picture, the new microscope uses quantum technology to reduce random light fluctuations within an image. It works involving quantum entanglement, a phenomenon in which photons of light are linked to each other – an effect Einstein described as “spooky interaction at a distance”.
The microscope studies molecular vibrations within a cell. “It basically tells you about what chemical bonds there are in particular regions of the cell,” said Bowen. “That’s been shown to be able to distinguish cancerous from healthy cells.”
“If this technique that’s being proposed can extract more information from using not as intense light levels, then I think it’s quite a profound outcome,” said Gibson.
Prof Dayong Jin at the University of Technology Sydney, who was not involved in the research, said it would take time for the new imaging technology to be broadly adopted.
Jin cites the 2014 Nobel prize–winning research as an example: it was first developed in the early 1990s, but took more than a decade to be adopted in laboratories around the world.
“Hopefully within 10 years quantum microscopy can be widely developed and improved,” said Jin.
The researchers are hoping to further improve the performance of the new microscope, to give an image around 10 times clearer than existing technology.
Many governments around the world have invested heavily in quantum technology. The Australian Army Research Centre has identified it as having the potential for “unprecedented capabilities in sensing, imaging, communications and computing”. Developing sophisticated sensors such as this microscope also forms a key milestone in the UK’s quantum technologies roadmap.
In 2019, Google declared it had achieved “quantum supremacy” – that it had built a quantum computer capable of outperforming the world’s best traditional supercomputer.
The quantum microscopy research was partially funded by the US air force and was published in the prestigious journal Nature.