Scottish university tackles data security crisis with ‘breakthrough’ discovery in quantum networking

Researchers at Heriot-Watt University in Edinburgh have solved one of the fundamental problems facing quantum networking, making the innovative technology more affordable. 

“Data is the new currency and we need quantum networks to keep it secure. Our breakthrough will help accelerate the adoption of quantum networks and increase the security of our communications,” Professor Cristian Bonato, co-lead of Heriot-Watt’s quantum photonics laboratory, said. 

Quantum networks use single light particles that allow for unhackable communication channels, unlike internet connections that use light pulses travelling along a fibre cable. 

In other words, any eavesdropping on a channel would be intercepted as it would disturb the fragile single protons.  

 However, until now this innovative technology has been expensive to introduce. 

As atoms emit light at different frequencies, extra lasers and frequency-conversion equipment were needed for these “to talk to each other”, Bonato explained. 

 Funded by the European Commission and the UK Engineering and Physical Sciences Research Council (EPSRC), researchers have developed a new semiconductor system able to cut these costs. 

 By using single atoms that emit light at the same frequency, the system removes the need for additional equipment. 

Researchers have used the chemical element Vanadium in semiconductors to cut such expenses. This element has properties which emit light at a frequency compatible with standard telecommunication optical fibre networks, meaning organisations do not need to deploy new fibre to move to quantum networking.  

 Bonato said: “Each vanadium atom acts like a tiny antenna, which emits light at a given frequency.  

 “This antenna can be perturbed when heavier atoms are sitting nearby. For example, in nature, some silicon atoms are heavier than normal, as they host an additional neutron. A heavier atom nearby compresses the antenna, making it emit light at a slightly different frequency. We solved this problem by growing our semiconductor using identical silicon and carbon atoms.” 

  Vanadium atoms were tested in the semiconductor, silicon carbide.  

 Testing with this semiconductor was a “huge saving”, Boniato commented, as its use in electric vehicles means there are “standard manufacturing processes and knowledge of the material” readily available.  

The study, which featured a multi-national collaboration with scientists from Germany, Austria and Sweden, has now been published in the journal Nature Communications.