Scientists discover that a single atomic defect in 2D material can retain quantum information at room temperature

Scientists have discovered that a ‘single atom defect’ in a layered 2D material can retain quantum information for microseconds at room temperature, underscoring the potential of 2D materials in advancing quantum technologies.

The defect, discovered by researchers from the Universities of Manchester and Cambridge using a thin material called hexagonal boron nitride (hBN), demonstrates spin coherence – a property where an electronic spin can retain quantum information – under ambient conditions. They also discovered that these spins can be controlled with light.

So far, only a few solid-state materials have been able to do this, which represents an important step forward in quantum technology.

The findings, published in Natural materialsfurther confirm that the accessible spin coherence at room temperature is longer than the researchers initially thought it might be.

Carmem M. Gilardoni, co-author of the paper and postdoctoral researcher at the University of Cambridge’s Cavendish Laboratory, where the research was conducted, said: “The results show that as soon as we write a certain quantum state onto its spin, electrons become stores this information for ~1 millionth of a second, making this system a promising platform for quantum applications.

“This may seem short, but the interesting thing is that this system does not require any special conditions: it can store the spin-quantum state even at room temperature and without the need for large magnets.”

Hexagonal boron nitride (hBN) is an ultra-thin material consisting of stacked layers of one atom thick, a bit like sheets of paper. These layers are held together by forces between molecules, but sometimes there are small flaws between these layers called ‘atomic defects’, similar to a crystal in which molecules are trapped. These defects can absorb and emit light that we can see, and they can also act as local traps for electrons.

Because of the defects in hBN, scientists can now study how these trapped electrons behave, specifically the spin property, which allows electrons to interact with magnetic fields. They can also control and manipulate the electron spins using light within these defects at room temperature – something that has never been done before.

Dr. Hannah Stern, first author of the paper and Royal Society University Research Fellow and lecturer at the University of Manchester, said: “Working with this system has highlighted to us the power of fundamental research into new materials. Regarding the hBN system As a field, we can exploit the dynamics of excited states in other new material platforms for use in future quantum technologies.

“Each new promising system will broaden the toolkit of available materials, and each new step in this direction will advance the scalable implementation of quantum technologies.”

Professor Richard Curry added: “Research into materials for quantum technologies is vital to supporting the UK’s ambitions in this area. This work represents another leading breakthrough from a researcher at the University of Manchester in the field of materials for quantum technologies, increasing the international impact of our work in this area.”

Although there is still much to be researched before it is mature enough for technological applications, the discovery paves the way for future technological applications, especially in the field of sensor technology.

The scientists are still figuring out how to make these defects even better and more reliable and are currently investigating to what extent they can extend the spin storage time. They also investigate whether they can optimize the system and material parameters that are important for quantum technology applications, such as the stability of defects over time and the quality of the light emitted by this defect.