Guest Post: The Role of Silicon Photonics in Delivering Usable Quantum Computing

Guest post by Professor Callum Littlejohns, Deputy Director at CORNERSTONE, and Dr Amit Agrawal, Associate Professor in Optical Engineering at the University of Cambridge

The ability to scale is one of the most pressing issues in quantum hardware today, and solving scaling challenges has become a driving force behind significant government investments. This includes the UK government’s £2.5 billion Quantum Strategy – a 10-year plan for deploying the world’s first scaled quantum computers.

But to understand how to achieve scaled quantum systems, we need to look outside of the quantum discipline, to other tried-and-tested technologies.

In many ways, the quantum scaling challenge mirrors those faced by other industries before it: larger systems require more hardware, which means more complexity. However, quantum systems differ in that system stability relies on protecting delicate quantum states from the slightest disturbances to maintain coherence, increasing the complexity of the challenge. The hardware is constantly evolving, and as you add more components, this isolation is harder to maintain. Not to mention that you quickly run into other problems like added heat, latency, alignment complexity, and packaging challenges.