Quantum technologies are new, disruptive technologies that have the potential to outperform familiar information technologies, for example in the areas of communications, sensing, measurement and computing.  We all use all this stuff every day, relying on it increasingly as our lives become more and more "high-tech".  Quantum technologies employ the weird and counter-intuitive features of quantum physics in technologies that can offer greater security for communications and data, or in technologies that can measure and sense things better.  Or in technologies that can open up new and more powerful directions in computing.

The Quantum Communications Hub received an initial £24m of funding during its first phase (2014-2019), and £2m of additional capital equipment funds towards the extension of the Hub’s UK Quantum Network.  In 2019, the Hub was awarded a further £23.5M of government funding to enable the continuation of its expanded programme of work for a further five years (the so-called Phase 2 of the National Programme, 2019-2024).

Our proposed contribution to this endeavour is a Hub for new Quantum Communications Technologies.  Data and communications security are absolutely essential throughout society today - for individuals, institutions, businesses, governments and nations.  Current secure communications systems have vulnerabilities, some exposed today and others that may be exposed in the future as computing power and hacking techniques improve. Secure communications based on quantum physics can eliminate some of these vulnerabilities, providing systems whose security is underpinned by the laws of Nature.  The basic features of quantum physics that enable secure communications are: (i) information encoded in a quantum system cannot be copied; (ii) information encoded in a quantum system is irreversibly changed when somebody reads it.  Intuitively, one can see that these cts will ensure that eavesdroppers on quantum communications always get caught. This can be utilised in quantum communications systems to give a guarantee of security.  The "classic" example is that Alice and Bob can share a secure, secret key, with a quantum promise that Eve knows nothing about it.  They can then use this key to protect a range of communications and transactions in the future.  However, they do have to consume the key to maintain security, so there is a need for topping up of secure key (quantum key distribution, or QKD) on a regular basis through quantum means.

Demonstrations of quantum communications systems have existed for a number of years now, but with limitations on their capabilities that have prevented large scale commercialisation of these technologies.  The grand vision of our Hub is to develop new quantum communications technologies that will overcome these limitations, enabling widespread use and adoption, from government and commerce through to consumers and the home.  We aim to develop short-range, low cost QKD for mobile devices such as 'phones.  We aim to develop chip-scale QKD modules for ease of manufacture and widespread and versatile deployment.  We aim to demonstrate QKD over networks and its integration with conventional communications.  We also aim to investigate new directions in quantum communications going beyond simple QKD, for example to quantum versions of digital signatures for signing electronic messages or documents.

There is great potential for the UK to become a world-leader across a range of new, high-tech, quantum technologies.  Furthermore, the quantum communications sector is of particular national importance.  As all security and cryptography technologies are sensitive and subject to import/export controls, it is therefore vital for the UK to establish "sovereign capability" in a new quantum communications sector.  We have assembled an outstanding team of scientists and engineers in our Hub to pursue this goal.