Developing compact tuning fork thermometers for sub-mK temperatures and high magnetic fields

What is it about?

We demonstrate that thermometers based on quartz tuning forks – the same resonators that keep time in a typical wrist watch – immersed in liquid helium-3 can be used to measure temperature in the combined experimental extremes of temperatures near 1 mK and high magnetic fields. We are also developing miniature thermometers based on this technique that make this technology more widely available.

Featured Image

Photo by Daniele Levis Pelusi on Unsplash

Photo by Daniele Levis Pelusi on Unsplash

Why is it important?

Measuring temperature, although straightforward at room temperature, becomes extremely difficult near absolute zero. If the object being measured is a small crystal that is also subject to a high magnetic field, there are limited options for temperature measurements, which are required to determine quantities like heat capacity or thermal conductivity. These can help identify phenomena such as superconductivity, which appear at low temperature and are important for characterizing materials to be used in applications such as quantum computing.