Regensburg 2025 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

MA: Fachverband Magnetismus

MA 31: Poster II

MA 31.7: Poster

Wednesday, March 19, 2025, 17:00–19:30, P1

Inverse magnetocaloric effect in Tb₃Ni: So hot right now — •T. Niehoff^{1, 2}, B. Beckmann³, K. Skokov³, A. Herrero⁴, A. Oleaga⁵, M. Straßheim^{1, 2}, T. Wosnitza^{1, 2}, and T. Gottschall¹ — ¹Dresden High Magnetic Field Laboratory (HLD-EMFL), HZDR, Dresden, Germany — ²Institut für Festkörper- und Materialphysik, TU Dresden, Dresden, Germany — ³Institut für Materialwissenschaft, TU Darmstadt, Darmstadt, Germany — ⁴Departamento de Física Aplicada, UPV/EHU, Vitoria-Gasteiz, Spain — ⁵Departamento de Física Aplicada, UPV/EHU, Bilbao, Spain

The magnetocaloric effect (MCE) is a cornerstone of promising, environmentally friendly cooling technologies, particularly for cryogenic applications. In this presentation, we use Tb₃Ni as a case study, previously reported to exhibit a strong inverse MCE at very low temperatures based on magnetization measurements. By comparing these findings with other techniques, we show that neither Tb₃Ni nor similar materials with metamagnetic transitions from antiferromagnetic to ferromagnetic exhibit the predicted inverse effect. To support our claims and further investigate the MCE, we conducted specific-heat measurements and direct T_ad in pulsed-field experiments. These reveal no effects, while the pulsed-field data even show a significant positive effect, which we attribute to dissipative heating. Our findings highlight the importance of using complementary measurement techniques to accurately characterize the MCE and fully understand the behavior of these materials.

Keywords: High magnetic fields; magnetocaloric effect; Rare-earth