Just a few, short years ago, quantum technologies were seen as scientifically interesting but somewhat exotic topics of academic research. Today, they are attracting significant amount of public and private investment with a rapidly growing commercial sector. In the UK, a successful 10?year £1billion National Quantum Technology Programme (NQTP) has helped bring forth a thriving ecosystem comprising a large number of companies as well as many leading academic research groups. Focus has now firmly shifted from basic science to real-world, practical use and commercialisation.
The National Physical Laboratory (NPL) is the UK's national measurement institute (NMI). NPL's role in the UK's quantum ecosystem is twofold: to support the quantum sector with technical expertise and test and measurement solutions, and to address the measurement challenges limiting the scaling up of quantum technologies. As with any technology, accurate, well-understood measurements are crucial when implementing quantum systems and we are seeing an increasing need from industry for solutions tailored for their specific uses.
NPL is involved in all quantum technologies that are part of the NQTP: computing, networking, PNT (position, navigation and timing), sensing and materials. Some of these, such a timing, are closely linked to areas where NMIs have historically been leading, whereas some, such as quantum computing, are new to the metrology community. For these, significant effort is now going into developing best-practice for measurements of key parameters, traceable calibration methods and the measurement services that the growing quantum industry will need in the future.
It is important to stress that many urgent measurement challenges are not necessarily “quantum” in nature but are about adapting and extending existing methods to the extreme conditions (such as very low signal levels, ultra‑high vacuum or cryogenic temperatures) where quantum devices and systems operate. For example, NPL has developed techniques for t raceable calibration of microwave components at the ultra-low temperatures where superconducting quantum computers work. These systems are controlled using microwave signals (frequencies similar to those used for 5G)and large systems already require hundreds of control lines. As these systems continue to scale up, access to well characterised components and sub‑systems will become increasingly important, meaning there is an urgent need for accurate calibration methods. NPL’s expertise in both microwave metrology and superconducting quantum computing makes us well‑placed to lead in this area.
There are cases where new areas of metrology need to be created. While using quantum computers for real‑world problems are still some way off, there is already a thriving commercial sector with customers willing to pay for access to the latest hardware and investors putting their money into promising companies. Access to metrics that allow stakeholders to compare and evaluate different offerings are therefore already important. Many different metrics have been developed, and some are in common use. However, in many cases there are several ways to implement a given benchmarking method which sometimes give different results. Differences are often small and, for example, may not be relevant in a scientific publication. However, when building a large system or making investment decisions,even small differences can be significant. Again, NPL’s experience as an NMI combined with advanced research capabilities make us well placed to contribute.
Efforts to create international standards for quantum technologies, such as those led by IEC/ ISO and CEN‑CENELEC, are gaining momentum. Many of these new standards will concern characterisation and benchmarking methods and NPL, along with other NMIs, is playing an important role.
Recently, NPL with UK partners published a review of metrics and benchmarks for quantum computers, which was commissioned by the National Quantum Computing Centre. In late 2025, NPL together with a group of leading NMIs will launch NMI-Q, an initiative focused on develop a framework for pre‑standardisation efforts for quantum technologies.
As quantum technologies continue to develop, so will the need for accurate measurements. NPL, together with our UK and international partners, intends to make sure that the metrology keeps pace.
