First prototype of an interferometer for measuring the coefficient of thermal expansion :
Measuring the CTE (coefficient of thermal expansion) from 300 to 20K requires non-contact measurement. We have developed a laser interferometer to measure thermal expansion, which is essential for calibrating thermo-physical properties such as conductivity or heat capacity, which are dimensional and volumetric quantities.
The device eliminates the thermal expansion of the various materials making up the interferometer, because we have a zero-sum thickness between the sample and the two reference mirrors. There is still some development to do before the first measurements, which will take place in 2025.
Measurements will be taken using a camera coupled to a Python programme that recognises the shape of the interference fringes.
This data will be crucial for the storage of liquid hydrogen.