The University of Warwick and QuantIC researchers at Heriot Watt University and the University of Glasgow performed a study in optical sensing, which could considerably enhance the precision of measuring nanoscopic structures.

QuantIC is part of the UK National Quantum Technologies Program and is the UK Quantum Technology Hub in Quantum Enhanced Imaging.

The researchers used pairs of photons, which are essential components of energy that make up light, to develop a method that determines the thickness of objects that are less than a 100,000th of the width of a human hair.

In the latest technique, two near-identical photons are fired onto a component called a beamsplitter and their subsequent behavior is monitored – with some 30,000 photons detected every second, and 500bn in use during an entire experiment.

Identical photons tend to ‘buddy up’ and continue to travel together – the outcome of a mild quantum interference effect. As a result of this, the team’s newly developed setup provides the same stability and precision as current one-photon methods that, owing to the equipment needed, are more expensive.

Providing a host of promising applications, such as research to better understand DNA, cell membranes, and even quality control for nanoscopic 2D materials of one atom’s thickness, for example, graphene, the latest study represents a major improvement on current two-photon techniques with up to 100 times better resolution.