Scientists discover that single atom defects in 2D material can store quantum information at room temperature

Scientists have found that a “single atomic defect” in a layered 2D material can capture quantum information for microseconds at room temperature, highlighting the potential of 2D materials to advance quantum technologies.

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

This has so far only been possible with a few solid-state materials, which represents a significant advance in quantum technology.

The results, published in Natural materialsfurther confirm that the accessible spin coherence at room temperature is longer than the researchers initially assumed.

Carmem M. Gilardoni, co-author of the paper and a postdoctoral fellow at the Cavendish Laboratory at the University of Cambridge, where the research was carried out, said: “The results show that once we write a particular quantum state onto the spin of these elements, we do the following.” Electrons will store this information for about a millionth of a second, making this system a promising platform for quantum applications.

“That 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 without the need for large magnets.”

Hexagonal boron nitride (hBN) is an ultrathin material made of stacked, one-atom-thick layers, similar to sheets of paper. These layers are held together by forces between the molecules, but sometimes there are tiny imperfections between these layers, called “atomic defects,” similar to a crystal with molecules trapped inside. 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, particularly the spin property that allows electrons to interact with magnetic fields. They can also control and manipulate the electron spins using light in these defects at room temperature – something that has never been possible before.

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

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

Prof Richard Curry added: “Researching materials for quantum technologies is vital to supporting the UK’s ambitions in this area. This work represents another leading breakthrough by a University of Manchester researcher in the field of materials for quantum technologies and strengthens the international impact of our work in this area.

Although there is still much to be explored before it is ready for technical applications, the finding paves the way for future technological applications, particularly in sensing.

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