Distributed computation on a NISQ era quantum internet

The development of a quantum internet is hoped to be realised in the coming decades. A quantum internet should be able to run applications such as secure long-distance communication and be able to facilitate distributed algorithm by allowing resource-limited quantum computers to work collaboratively. Recent experimental developments in quantum networks have shown entanglement distribution between multiple parties. This opens the possibility of running distributed versions of quantum algorithms. However, current networks have a low rate of entanglement, are constrained by limits in quantum memory and operations performed on a quantum computer add noise. Therefore, for an application to be useful with current devices, it must be able to operate with minimal communication, as well as being robust to noise.

The project will investigate two main areas of research around quantum networks: the distribution of entanglement between multiple users and how distributed algorithms could operate in the near term. Initially the feasibility of sharing quantum entanglement between many users in a network will be assessed. This will be tested using numerical simulations and realistic network parameters. This means assessing a network where most users have minimal functionality due to hardware constraints, and how the entanglement rate of the network can be maximised despite these limitations. Next, the applications which could be run on these networks will be assessed. The effectiveness of a distributed approach for quantum algorithms will be quantified and compared to a single user approach.

The first and most important impact of our Centre will be through the cross-disciplinary technical training it provides for its students. Through this training, they will have not only skills to control and exploit quantum physics in new ways, but also the background in device engineering and information science to bring these ideas to implementation and to seek out new applications. Our commercial and governmental partners tell us how important these skills are in the growing number of people they are hiring in the field of quantum technologies. In the longer term we expect our graduates to be prominent in the development of new technologies and their application to communication, information processing, and measurement science in leading university and government laboratories as well as in commercial research and development. In the shorter term we expect them to be carrying out doctoral research of the highest international quality.

Second, impact will also flow from the students' approach to enterprise and technology transfer. From the outset they will be encouraged to think about the value of intellectual property, the opportunity it provides, and the fundraising needed to support research and development. As students with this mindset come to play a prominent part in university and commercial laboratories, their common background will help to break down the traditional barriers between these sectors and deliver the promise of quantum technologies for the benefit of the UK and world economies. Concrete actions to accelerate this impact will include entrepreneurship training and an annual CDT industry day.

Third, through the participation it nucleates in the training programme and in students' research, the Centre will bring together a community of partners from industry and government laboratories. In the short term this will facilitate new collaborations and networks involving the partners and the students; in the long term it will help to ensure that the supply of highly skilled people from the CDT reaches the parts of industry that need them most.

Finally, the CDT will have a strong impact on the quantum technologies training landscape in the UK. The Centre will organise training events and workshops open to all doctoral researchers to attend. We will also collaborate with CDTs in the quantum technologies and related research areas to coordinate our efforts and maximise our joint impact. Working in consort, these CDTs will form a vibrant national training network benefitting the entire UK doctoral research community.