System scalability is sought across various hardware platforms and is essential for large-scale quantum computers (QCs). Architectures such as the Quantum Charge-Coupled Device (QCCD) are used to grow the number of qubits on a single device for QCs based on trapped ions. However, the size of the chip used limits the number of ions that can be accommodated on a single quantum computer module. A modular approach is therefore crucial and requires quantum couplings between different components.

For the first time, researchers from the University of Sussex and Universal Quantum have successfully and quickly demonstrated that quantum bits (qubits) can be transferred directly across microchips of quantum computers. This innovation removes a major barrier to building quantum computers large and powerful enough to address challenging issues vital to society.

In this study, researchers used a new and powerful technique called UQ Connect to use electric field couplings to enable qubits to move from one quantum computing microchip module to another with unprecedented speed and precision. As a result, chips can be put together like puzzle pieces to create a more powerful quantum computer.

The researchers transported the qubits with a success rate of 99.999993% and a connection speed of 2424/s. Both numbers are world records and orders of magnitude better than previous solutions.

Professor Winfried Hensinger, Professor of Quantum Technologies at the University of Sussex and Chief Scientist and co-founder of Universal Quantum, said: “While we linked the modules together at world-record speed, we also verified that the “strange” quantum nature of the qubit remains untouched during transport, for example that the qubit can be both 0 and 1 at the same time.”

Dr. Sebastian Weidt, CEO and co-founder of Universal Quantum and Senior Lecturer in Quantum Technologies at the University of Sussex, said: “Our relentless focus is on providing people with a tool to revolutionize their field of work. The Universal Quantum and University of Sussex teams have done something truly incredible here that will help make our vision a reality. These exciting results demonstrate the remarkable potential of Universal Quantum’s quantum computers to become powerful enough to unlock the many life-changing applications of quantum computing.”

Dr. Mariam Akhtar led the research as Research Fellow at the University of Sussex and Quantum Advisor at Universal Quantum. She said, “The team has demonstrated fast and coherent ion transfer using quantum matter links. This experiment validates the unique architecture developed by Universal Quantum and offers an exciting route to truly large-scale quantum computing.”

Professor Sasha Roseneil, Vice-Chancellor of the University of Sussex, said: “It is fantastic to see the inspired work of the University of Sussex and Universal Quantum physicists have resulted in this phenomenal breakthrough, bringing us an important step closer to a quantum computer that will be of real benefit to society.”

“These computers will have limitless applications – from improving drug development, creating new materials to perhaps even unlocking solutions to the climate crisis. The University of Sussex is investing heavily in quantum computing to support our bold ambition to build the most powerful to host quantum computers in the world and bring about change that can positively impact so many people around the world.”

“And with teams spanning the spectrum of quantum computing and technology research, the University of Sussex has both breadth and depth of expertise. We continue to expand our research and teaching in this area, with plans for new teaching programs and appointments.

Professor Keith Jones, Interim Provost and Pro Vice-Chancellor for Research and Enterprise at the University of Sussex said: “This is a fascinating finding from our University of Sussex and Universal Quantum physicists. It proves the value and dynamism of this University of Sussex spin-out company, whose work is based on rigorous and world-leading academic research. Quantum computing will be crucial in helping solve some of the most pressing global problems.”

Magazine reference:

  1. M. Akhtar et al., A high-fidelity quantum matter-link between ion-trap microchip modules, Nature Communications (2023). DOI: 10.1038/s41467-022-35285-3