Interfacial Mixing Effect in a Promising Skyrmionic Material: Ferrimagnetic Mn4N

Published

August 24, 2022

Author(s)

Chung T. Ma, Brian Kirby, S. J. Poon

Abstract

Interfacial mixing of elements is a well-known phenomenon found in thin film deposition. For thin-film magnetic heterostructures, interfacial compositional inhomogeneities can have drastic effects on the resulting functionalities. As such, care must be taken to characterize the compositional and magnetic properties of thin films intended for device use. Recently, ferrimagnetic Mn₄N thin films have drawn considerable interest due to exhibiting perpendicular magnetic anisotropy, high domain-wall mobility, and good thermal stability. In this study, we employed X-ray photoelectron spectroscopy (XPS) and polarized neutron reflectometry (PNR) measurements to investigate the interfaces of an epitaxially-grown MgO/Mn₄N/Pt trilayer deposited at 450 °C. XPS revealed the thickness of elemental mixing regions of near 5 nm at both interfaces. Using PNR, we found that these interfaces exhibit essentially zero net magnetization at room temperature. Despite the high-temperature deposition at 450 °C, the thickness of mixing regions is comparable to those observed in magnetic films deposited at room temperature. Micromagnetic simulations show that this interfacial mixing should not deter the robust formation of small skyrmions, as revealed by micromagnetic simulations, consistent with a recent experiment. The results obtained are encouraging in terms of the potential of integrating thermally stable Mn4N into future spintronic devices.

Citation

AIP Advances

Volume

12

Issue

8

Pub Type

Journals

Download Paper

DOI Link

Keywords

neutron

Citation

Ma, C. , Kirby, B. and Poon, S. (2022), Interfacial Mixing Effect in a Promising Skyrmionic Material: Ferrimagnetic Mn₄N, AIP Advances, [online], https://dx.doi.org/10.1063/5.0109005 (Accessed April 28, 2024)