Aalto University researchers propose a method to convert the frequency to power.

In 2019, the International System of Units (SI) was renamed to become the world’s most widely used system of measuring. Since then, units have been defined using the constants in Nature, that is, Nature’s rules which are set and cannot be changed, like the speed of light. Not in terms of random references.

This has led to new research that aims to relate the system’s various units with the constants via experimental realizations.

Professor Jukka Perkola says, “The redefinition caused a need to new realizations.”

Aalto University researchers have discovered a promising way to link the unit of power, the watt, to the constants in Nature. Their method may lead to a new power standard. It is a way to generate an apriori-known amount of power that can be used to compare other power sources. Frequency can be defined as a quantity with low uncertainty. It provides a solid foundation for a new standard.

Frequency can be very precisely defined. Pekola states that if you can make other quantities dependent on frequency in a well-defined way, you have an extremely accurate standard.”

Researchers also discovered that such dependence is governed by a simple, robust and accurate law.

These characteristics increase the likelihood of using this method to set a standard,” Marco Marin Suarez (a doctoral candidate) says.

Marin Suarez says, “Basically, it’s a new way to realize a watt or energy flux just by setting previously unknown quantities.”

The experiment shows that power can be produced using a single electron transistor’s turnstile operation. Pekola had previously proven that this device could be used as a standard for the ampere (the unit of electrical current). It comprises a small metallic island, source and drain leads, and a gate electrode. It can handle very little power.

It takes a long time to go from a proposal to an accepted standard. The Aalto researchers believe their work will be next noticed by metrologists who want to take it further and use more precise measurements.

The first experiment did not reach the level of metrology. However, we demonstrated that the principle worked and showed where the major errors were. “It remains to be seen whether this is adopted by metrology communities,” Pekola concludes.

Researchers now want to advance their proposal by determining how frequency to power conversion law adapts to their method. This will improve the precision at which small power can be calibrated.