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  • Abnormal Magnetic Phase Transition in Mixed‐Phase (110)‐Oriented FeRh Films on Al 2 O 3 Substrates via the Anomalous Nernst Effect
Title: Abnormal Magnetic Phase Transition in Mixed‐Phase (110)‐Oriented FeRh Films on Al 2 O 3 Substrates via the Anomalous Nernst Effect
Abstract Iron rhodium (FeRh) undergoes a first‐order anti‐ferromagnetic to ferromagnetic phase transition above its Curie temperature. By measuring the anomalous Nernst effect (ANE) in (110)‐oriented FeRh films on Al2O3substrates, the ANE thermopower over a temperature range of 100–350 K is observed, with similar magnetic transport behaviors observed for in‐plane magnetization (IM) and out‐of‐plane magnetization (PM) configurations. The temperature‐dependent magnetization–magnetic field strength (M–H) curves revealed that the ANE voltage is proportional to the magnetization of the material, but additional features magnetic textures not shown in the M‐H curves remained intractable. In particular, a sign reversal occurred for the ANE thermopower signal near zero field in the mixed‐magnetic‐phase films at low temperatures, which is attributed to the diamagnetic properties of the Al2O3substrate. Finite element method simulations associated with the Heisenberg spin model and Landau–Lifshitz–Gilbert equation strongly supported the abnormal heat transport behavior from the Al2O3substrate during the experimentally observed magnetic phase transition for the IM and PM configurations. The results demonstrate that FeRh films on an Al2O3substrate exhibit unusual behavior compared to other ferromagnetic materials, indicating their potential for use in novel applications associated with practical spintronics device design, neuromorphic computing, and magnetic memory.  more » « less
Award ID(s):
2230352
PAR ID:
10556111
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Small
Volume:
20
Issue:
43
ISSN:
1613-6810
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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