Physical Aspects of the Functionalities of Heusler-based Compounds and an Outreach to new Functionalities

by Mehmet Acet

Tuesday Jan 20, 2026, 4:15 PM → 5:45 PM Europe/Berlin

H6 (UHG)

Heuslers have a history that runs back to a century, and even a little more. They have never retired and are still materials of interest for both the physics and the materials science communities. One of the first use of Heusler compounds was as monochromators and polarizers used in experimental beamlines at neutron facilities. After the discovery of the
occurrence of martensitic phase transitions is some Heuslers, interests in the exploitation of these structural phase transitions grew even further in the direction of shape-memory, magnetic shape-memory, magnetocaloric effects, energy harvesting, and many more. Roughly 50 years after the discovery of Heuslers, Half-Heuslers we discovered which eventually brought along with it the possibility of attaining 100% conduction electron spin-polarization, which is a phenomenon that is currently being exploited for spintronic applications.
Out of these diverse and rich functionalities, we firstly focus here on the physics of the first order magnetostructural phase transition properties of Ni-Mn-based Heuslers, particularly in relation to the magnetocaloric effect. We not only present the magnetocaloric properties themselves but also try to recognize what the magnetocaloric effect teaches us physically on
magnetostructural phase transitions through experimental findings. Our second focus is on a newly emerging property where off-stoichiometric Heuslers segregate into a stoichiometric ferromagnet and a stoichiometric antiferromagnetic component and give rise to strong magnetic pinning effects in both Heuslers and Half-Heuslers allowing the research to reach out to new functionalities. Such findings suggest that the room for the discovery of new functionalities of these materials is not exhausted.

2026-01-20-Prof.MehmetAcet.pdf