Antiferromagnetic-ferromagnetic phase domain development in nanopatterned FeRh islands

Abstract

The antiferromagnetic to ferromagnetic phase transition in B2-ordered FeRh is imaged in laterally confined nanopatterned islands using photoemission electron microscopy with x-ray magnetic circular dichroism contrast. The resulting magnetic images directly detail the progression in the shape and size of the FM phase domains during heating and cooling through the transition. In 5 um square islands this domain development during heating is shown to proceed in three distinct modes: nucleation, growth, and merging, each with subsequently greater energy costs. In 0.5 um islands, which are smaller than the typical final domain size, the growth mode is stunted and the transition temperature was found to be reduced by 20 K. The modification to the transition temperature is found by high resolution scanning transmission electron microscopy to be due to a 100 nm chemically disordered edge grain present as a result of ion implantation damage during the patterning. FeRh has unique possibilities for magnetic memory applications; the inevitable changes to its magnetic properties due to subtractive nanofabrication will need to be addressed in future work in order to progress from sheet films to suitable patterned devices.

References in corpus (6)

• Room-temperature antiferromagnetic memory resistor
• Full Electroresistance Modulation in a Mixed-Phase Metallic Alloy
• Room temperature write-read operations in antiferromagnetic memory
• Colossal magnetic phase transition asymmetry in mesoscale FeRh stripes
• Observation of a temperature dependent asymmetry in the domain structure of a Pd doped FeRh epilayer
• Modulating the phase transition temperature of giant magnetocaloric thin films by ion irradiation

Cited by in corpus (4)

• Fast Pixelated Detectors in Scanning Transmission Electron Microscopy. Part II: Post Acquisition Data Processing, Visualisation, and Structural Characterisation
• Asymmetric Magnetic Relaxation behavior of Domains and Domain Walls Observed Through the FeRh First-Order Metamagnetic Phase Transition
• Direct visualization of the magnetostructural phase transition in nano-scale FeRh thin films using differential phase contrast imaging
• Phase Boundary Exchange Coupling in the Mixed Magnetic Phase Regime of a Pd-doped FeRh Epilayer