Quantitative TEM imaging of the magnetostructural and phase transitions in FeRh thin film systems

DOI: 10.1038/s41598-017-18194-0

Authors: Trevor P. Almeida (University of Glasgow) , Rowan Temple (University of Leeds) , Jamie Massey (University of Leeds) , Kayla Fallon (University of Glasgow) , Damien Mcgrouther (University of Glasgow) , Thomas Moore (University of Leeds) , Christopher H. Marrows (University of Leeds) , Stephen Mcvitie (University of Glasgow)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Scientific Reports , VOL 7

State: Published (Approved)
Published: December 2017

Abstract: Equi-atomic FeRh is a very interesting material as it undergoes a magnetostructural transition from an antiferromagnetic (AF) to a ferromagnetic (FM) phase between 75–105 °C. Its ability to present phase co-existence separated by domain walls (DWs) above room temperature provides immense potential for exploitation of their DW motion in spintronic devices. To be able to effectively control the DWs associated with AF/FM coexistence in FeRh thin films we must fully understand the magnetostructural transition and thermomagnetic behaviour of DWs at a localised scale. Here we present a transmission electron microscopy investigation of the transition in planar FeRh thin-film samples by combining differential phase contrast (DPC) magnetic imaging with in situ heating. We perform quantitative measurements from individual DWs as a function of temperature, showing that FeRh on NiAl exhibits thermomagnetic behaviour consistent with the transition from AF to FM. DPC imaging of an FeRh sample with HF-etched substrate reveals a state of AF/FM co-existence and shows the transition from AF to FM regions proceeds via nucleation of small vortex structures, which then grow by combining with newly nucleated vortex states into larger complex magnetic domains, until it is in a fully-FM state.

Journal Keywords: Magnetic properties and materials; Phase transitions and critical phenomena

Diamond Keywords: Ferromagnetism

Subject Areas: Physics, Materials


Technical Areas:

Added On: 23/01/2018 14:52

Documents:
s41598-017-18194-0.pdf

Discipline Tags:

Surfaces Quantum Materials Physics Magnetism Materials Science interfaces and thin films

Technical Tags: