Experts make new approach to accurately defining the SI unit of power awarded QTF Annual Discovery Prize

Each year, the Quantum Technology Finland Centre of Excellence recognizes a groundbreaking scientific achievement by one of its members with the QTF Annual Discovery Prize. This year the winner is Marco Marín-Suárez, doctoral researcher at the Quantum Phenomena and Devices (PICO) group at the Department of Applied Physics.

Metrology is the science of measurement, and it hinges on finding improved ways of defining key measurement units for fundamental physical quantities. Marín-Suárez is awarded for discovering a new approach to realizing a standard for power in experimental setups. Marín-Suárez is the lead author of the winning scientific paper titled “An electron turnstile for frequency-to-power conversion”, published in Nature Nanotechnology in 2022.

“In this work, we employed a hybrid single-electron turnstile, a platform used in the past for realizing a standard for the unit of electrical current, to emit electrons one-by-one at a known rate with well-defined energy. This enabled the production of precise, controllable amounts of power. In the newly revised SI, these kinds of demonstrations show that units can be experimentally realized according to their new definitions in terms of physical constants. Now, the challenge resides in showing that higher accuracies can be achieved in more simplified setups.”

In the study, Marín-Suárez and the team used a hybrid single-electron transistor to link a frequency to power. The result is an approach that, under optimal conditions, can have an error rate well below one percent from ideal frequency-to-power conversion. The experimental work paves the way for an alternative, more precise approach to the power standard, which promises to have a range of applications in quantum thermodynamics and detection of superconducting excitations.

“Me and my coauthors, doctors Joonas Peltonen and Dmitry Golubev as well as Professor Jukka Pekola, knew of the impact of this study. However, we were not expecting such an acknowledgment. This prize is a great boost to my career which I will continue in the industry for the time being, pending, of course, my defense.”

Marín-Suárez is set to defend his doctoral thesis on the topic at Aalto University on July 4.

The QTF Annual Discovery Prize winner was decided by a panel of three distinguished judges: Prof. Erik Aurell of the KTH Royal Institute of Technology, prof. Robert Fickler of the University of Tampere and prof. Anasua Chatterjee, the University of Copenhagen. The prize, totaling a thousand euros, was awarded today at the QTF Summer Day event.