An international study led by the University of Southampton has demonstrated for the first time how light can be used to glue together negative charges and create a novel form of matter.

The ground-breaking research, led by Physics and Astronomy's Professor Simone De Liberato, opens new possibilities for engineering novel artificial atoms with designer electronic configurations.

Researchers built upon a theoretical prediction from 2019 to fabricate a nanodevice that trapped electrons within nanoscopic wells.

When photons struck the device with a high enough energy they would extract electrons from the wells. The team then enclosed the device between two gold mirrors, dramatically increasing the interaction between light and matter.

The study observed that a negatively-charged electron would remain trapped, bound to the other negatively-charged electrons in a novel electronic configuration like a 'subatomic zip tie' stabilised by the photon.

Scientists have published their findings in the journal Nature Physics.

The technique will be used to broaden the catalogue of materials available to design photonic devices.

Read the full story on the main news page.

Researchers from the University of Southampton are adapting imaging techniques used to study stars and galaxies to create medical camera systems that use lower doses of radiation.

Physics and Astronomy's Professor Tony Bird is working with specialists at University Hospital Southampton and University spin-out company Symetrica to develop the gamma-ray imaging that will improve the effectiveness of nuclear medicine.

Nuclear medicine is a specialised area of radiology that uses very small amounts of radioactive materials to examine organ function and structure using imagery from sensitive gamma-ray detectors.

Professor Bird, of the Southampton Astronomy Group, says: "The imaging systems we are using were developed for gamma-ray astronomy, where we try to study emissions from distant stars and galaxies. Because those emissions are so faint, our imaging systems (called 'coded masks') are designed to catch every gamma ray they can and are much more efficient than current collimators."

The collaboration is funded through the SPace Research and Innovation Network for Technology (SPRINT).

The University has also developed new software that can deal with a moving camera or patient, based on astronomical imaging allowing a telescope to move across the sky while still collecting information.

Read the full story in the latest edition of Re:action, the University's research and enterprise magazine.

Space physicist Dr Daniel Whiter is investigating the impact on our planet of the huge amounts of energy brought into our atmosphere by the aurora borealis, or Northern Lights.

The researcher at the University of Southampton is one year into a five-year fellowship from the Natural Environment Research Council.

The Northern Lights are caused by charged particles from space colliding with gas particles in the Earth’s atmosphere at 40 million miles per hour.

In order to understand how this energy impacts our planet and whether it could even be affecting our climate, Daniel is developing novel techniques to measure the temperature at auroral heights. This has never been done accurately before, as the altitude is too high for weather balloons but too low for spacecraft.

He is using sensitive cameras equipped with colour filters to map atmospheric temperature, similar to a thermal imaging camera. This is combined with radar measurements of the upper atmosphere to estimate the electrical conductivity, before a computer simulation helps understand how different types of aurora are produced, what electric currents they generate, and how the aurora affects the temperature and chemistry of the upper atmosphere.

“The aurora definitely heats the upper atmosphere,” Daniel says. “The Met Office is starting to expand its models to the upper atmosphere, as we are learning that there is more coupling between layers of the atmosphere than previously thought. We don’t know how it influences the Earth’s climate yet, but it’s something we, and the Met Office, want to understand.”

Read the full feature in the Summer 2020 edition of Re:action, the University’s research and enterprise magazine.