New applications for the world's smallest high-precision capacitance dilatometer and its stress-implementing counterpart

TL;DR

This paper presents a new, compact stress dilatometer with interchangeable parts, enabling high-resolution thermal expansion and magnetostriction measurements in cryogenic environments, including in situ rotation and ultra-low temperature conditions.

Contribution

The authors introduce a novel mini-dilatometer with an interchangeable body, allowing versatile high-resolution measurements in cryogenic systems and new applications in rotation and ultra-low temperature environments.

Findings

Successful installation in cryogen-free systems (PPMS DynaCool)

In situ rotation capability between -90° and +90°

Measurements at temperatures down to 0.06 K with 0.01 Å resolution

Abstract

We introduce a new stress dilatometer with exactly the same size and weight as the world's smallest miniature capacitance dilatometer (height x width x depth = 15 mmx14 mmx15 mm, weight: 12 g). To develop this new device, only a single part of the most recently developed mini-dilatometer, the so-called 'body', needs to be replaced. Therefore, the new mini dilatometer with an interchangeable body can be used for high-resolution measurements of thermal expansion and magnetostriction with and without large stress. We also report two novel applications of both mini-dilatometer cell types. Our new setup was installed for the first time in a cryogen-free system (PPMS DynaCool). The first new setup allows the rotation of both dilatometers in situ at any angle between -90 deg > {\mu} > +90 deg in the temperature range from 320 K to 1.8 K. We also installed our mini-cells in a dilution refrigerator insert of a PPMS DynaCool, in which dilatometric measurements are now possible in the temperature range from 4 K to 0.06 K. Because of the limited sample space, such measurements could not be performed so far. For both new applications, we can resolve the impressive length changes to 0.01 A.