The future quantum internet will be defined by speed, energy efficiency and security and offers revolutionary possibilities. As quantum computers become more powerful, sensitive data could be quickly intercepted and compromised by bad actors. Sophisticated encryption enabled by quantum key distribution (QKD) offers a solution – but these fast, secure communications links will rely on novel photonics technology, which QUDITS2 will demonstrate.
Such advances in quantum could lead to game-changing computing power, with the machines capable of performing beyond today’s most advanced supercomputers, potentially leading to breakthroughs in medicine and in the fields of AI and finance.
Qubits to qudits
During the initial feasibility study (QUDITS), the CSA Catapult research showed the possibility of moving from using qubits to qudits – higher dimensional states of quantum information that can carry more information. Unlocking this capability would create a disruptive and cutting-edge communications system, created using commercially available components within a sovereign UK supply chain.
The study demonstrated in the lab that using properties of light such as its orbital angular momentum (OAM), could lead to the development of commercial systems.
New commercial applications
The QUDITS2 consortium also aims to show a commercially feasible quantum communications system with real-world potential to advance future telecoms.
By bringing in commercially available capabilities from across the supply chain, QUDITS2 will show the hardware’s viability and its ability to be manufactured at comparatively lower cost. The system will make use of existing photonic crystal surface-emitting lasers (PCSELs) and low noise Avalanche Photo Diodes (APDs), which can operate at optical communications wavelengths.
PCSELs from Vector Photonics are novel, high-speed, low-cost systems that bring considerable advantages over other types of lasers used in OAM systems. Phlux Technology has developed an innovative and far more sensitive low-noise detector technology, while the University of Bristol offers a novel metasurface able to increase yield and the output of the PCSEL lasers used.
The key enabler in QUDITS2 is the use of miniature phase plates with the PCELS, meaning the design size can be compacted, and costs reduced.
Combined with the expertise in quantum commercialisation from CSA Catapult, QUDITS2 has the possibility of demonstrating large commercial benefit, with an estimated ROI of 75 times on public funding investment, while opening the door to making the UK a quantum communications pioneer.
