Developing Quantum Metrology – and Metrology for Quantum Technology

Quantum mechanics is an overarching theory in physics that describes the world on its smallest scale, at the particle and photon level. The advancements in the early 20th century laid the groundwork for much of the technology we take for granted today, including computers, lasers, mobile phones, and satellite navigation systems. By controlling and manipulating individual quantum systems such as single atoms or photons, we can develop entirely new technology. In a second quantum revolution, new technical possibilities are now being created such as quantum computers, interception-proof communication and – not least – extremely sensitive measuring instruments.

“Future will show which technical advancements prove successful. Few researchers in the early 20th century could have predicted that their research in quantum physics would enable the construction of atomic clocks, which in turn have created the conditions for global navigation systems like GPS", says Martin Zelan, a researcher in laser and atomic physics who also works on coordinating and developing the research conducted at the national laboratories at RISE.

Quantum Metrology for More Accurate Measurements

A significant part of the future research at the national laboratories involves quantum metrology, that is, using quantum mechanics to improve measurements of physical quantities such as time, mass, and current, more than what is possible with conventional measurement methods. This can be done by developing new measuring instruments and new ways of measuring. In the future, for example, we could be using extremely precise atomic clocks to measure elevation above sea level to the centimetre, based solely on the fact that time moves slower or faster depending on gravity. Another important issue is to make the new measuring instruments more accessible by reducing their size and cost. Using quantum mechanical phenomena, we can also develop more accurate references, creating even better conditions for conventional measurements.

“Together with new measuring instruments, this contributes to even more accurate measurements in industry and society, and ultimately to more efficient production and new scientific breakthroughs”, says Martin Zelan.

Quantum Mechanics is Already Used Daily

Even though some applications are a few years away, and some many years in the future, quantum mechanics is already present in the daily work at the national laboratories through atomic clocks, lasers, and quantum standards.

“Quantum mechanics is such a natural part of measurement technology that one might not think about it being quantum. We invested in the first quantum standards for the electrical units volt and ohm already in the 90s. But the revision of the SI system has created conditions for new initiatives within the field, which has contributed to our expertise and our investments growing in recent years, says Karin Cedergren”, researcher and manager of the unit for Temperature and Primary Electrical Metrology, and continues:

“There is also a growing interest from industry and society. Each year, the number of projects that include quantum mechanics within metrology research increases. Somewhere there's a limit to what can be done with classical measurement methods, and that limit has been reached in many areas. Quantum mechanics is needed to improve those measurements further.”

A Swedish Quantum Agenda

The Swedish Research Council, Vinnova, Swelife, the Wallenberg Center for Quantum Technology, and RISE have produced the report A Swedish Quantum Agenda. The report provides an overview of the current state of quantum technology in Sweden and what needs to be done to promote development and strengthen Sweden's position. This involves, among other things, strengthening Sweden's expertise in quantum technology to enhance our competitiveness. The government has also taken the initiative for a national quantum strategy. And even though quantum mechanics is already a natural part of measurement technology, the national laboratories at RISE also need to improve.

“Partly, of course, by using quantum mechanics to make even more accurate measurements. And partly by developing technology and methods that can support companies and organizations developing quantum technology with the accurate measurements required. Both developing quantum metrology and developing metrology that supports quantum technology. To do this, we need to continue building expertise through collaborations with Swedish and European colleagues”, says Martin Zelan.

The national laboratories collaborate with European and Swedish colleagues through, for example, the European metrology organization EURAMET's European Metrology Network for Quantum Technologies, the Swedish Quantum Sweden Innovation Platform, and through research projects with universities such as Chalmers, Lund University, and Umeå University. Examples of areas where we are already active and successful include the realization of the unit for resistance (ohm) using graphene and within pressure measurements based on quantum methods.

“But we need and want to do even more. To measure quantum computer components, one needs equipment that allows measurements at around 10 millikelvin, which requires further investments from our side. It would also be exciting to continue contributing to the development of quantum standards, such as for the current unit, ampere, by counting the number of electrons per unit of time”, says Karin Cedergren.

Want to Know More About the Needs

A Swedish Quantum Agenda also identifies standardization as an important area, where RISE has extensive experience and a unique role as an independent research institute. RISE also has a special focus on supporting small and medium-sized enterprises, which may not fully have the resources required to develop quantum technology within the company.

“As an independent research institute, we can work closely with industry and the business sector on different applications. We are very interested in knowing more about the needs for measurements supporting quantum development, so that we can shape our offerings accordingly”, says Karin Cedergren.