Interface composition between Fe3O4 nanoparticles and GaAs for spintronic applications

Sahar Hihath, Richard Kiehl, Klaus Van Benthem

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Recent interest in spintronic applications has necessitated the study of magnetic materials in contact with semiconductor substrates; importantly, the structure and composition of these interfaces can influence both device functionality and the magnetic properties. Nanoscale ferromagnet/semiconductor structures are of particular interest. In this study, the interface structure between a monolayer of ferromagnetic magnetite (Fe3O4) nanoparticles and a GaAs substrate was studied using cross-sectional transmission electron microscopy techniques. It was found that a continuous amorphous oxide interface layer separates the nanoparticles from the GaAs substrate, and that iron diffused into the interface layer forming a compositional gradient. Electron energy-loss near-edge fine structures of the O K absorption edge revealed that the amorphous oxide is composed of γ-Fe2O3 directly underneath the Fe3O 4 nanoparticles, followed by a solid solution of Ga2O 3 and FeO and mostly Ga2O3 when approaching the buckled oxide/substrate interface. Real-space density functional theory calculations of the dynamical form factor confirmed the experimental observations. The implication of the findings on the optimization of these structures for spin injection is discussed.

Original languageEnglish (US)
Article number084306
JournalJournal of Applied Physics
Volume116
Issue number8
DOIs
StatePublished - 2014
Externally publishedYes

Fingerprint

nanoparticles
oxides
space density
magnetic materials
magnetite
form factors
solid solutions
energy dissipation
fine structure
electron energy
injection
density functional theory
magnetic properties
iron
gradients
transmission electron microscopy
optimization

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Interface composition between Fe3O4 nanoparticles and GaAs for spintronic applications. / Hihath, Sahar; Kiehl, Richard; Benthem, Klaus Van.

In: Journal of Applied Physics, Vol. 116, No. 8, 084306, 2014.

Research output: Contribution to journalArticle

@article{a31bc46154af462e9fb545e1d90a87b4,
title = "Interface composition between Fe3O4 nanoparticles and GaAs for spintronic applications",
abstract = "Recent interest in spintronic applications has necessitated the study of magnetic materials in contact with semiconductor substrates; importantly, the structure and composition of these interfaces can influence both device functionality and the magnetic properties. Nanoscale ferromagnet/semiconductor structures are of particular interest. In this study, the interface structure between a monolayer of ferromagnetic magnetite (Fe3O4) nanoparticles and a GaAs substrate was studied using cross-sectional transmission electron microscopy techniques. It was found that a continuous amorphous oxide interface layer separates the nanoparticles from the GaAs substrate, and that iron diffused into the interface layer forming a compositional gradient. Electron energy-loss near-edge fine structures of the O K absorption edge revealed that the amorphous oxide is composed of γ-Fe2O3 directly underneath the Fe3O 4 nanoparticles, followed by a solid solution of Ga2O 3 and FeO and mostly Ga2O3 when approaching the buckled oxide/substrate interface. Real-space density functional theory calculations of the dynamical form factor confirmed the experimental observations. The implication of the findings on the optimization of these structures for spin injection is discussed.",
author = "Sahar Hihath and Richard Kiehl and Benthem, {Klaus Van}",
year = "2014",
doi = "10.1063/1.4893958",
language = "English (US)",
volume = "116",
journal = "Journal of Applied Physics",
issn = "0021-8979",
publisher = "American Institute of Physics Publising LLC",
number = "8",

}

TY - JOUR

T1 - Interface composition between Fe3O4 nanoparticles and GaAs for spintronic applications

AU - Hihath, Sahar

AU - Kiehl, Richard

AU - Benthem, Klaus Van

PY - 2014

Y1 - 2014

N2 - Recent interest in spintronic applications has necessitated the study of magnetic materials in contact with semiconductor substrates; importantly, the structure and composition of these interfaces can influence both device functionality and the magnetic properties. Nanoscale ferromagnet/semiconductor structures are of particular interest. In this study, the interface structure between a monolayer of ferromagnetic magnetite (Fe3O4) nanoparticles and a GaAs substrate was studied using cross-sectional transmission electron microscopy techniques. It was found that a continuous amorphous oxide interface layer separates the nanoparticles from the GaAs substrate, and that iron diffused into the interface layer forming a compositional gradient. Electron energy-loss near-edge fine structures of the O K absorption edge revealed that the amorphous oxide is composed of γ-Fe2O3 directly underneath the Fe3O 4 nanoparticles, followed by a solid solution of Ga2O 3 and FeO and mostly Ga2O3 when approaching the buckled oxide/substrate interface. Real-space density functional theory calculations of the dynamical form factor confirmed the experimental observations. The implication of the findings on the optimization of these structures for spin injection is discussed.

AB - Recent interest in spintronic applications has necessitated the study of magnetic materials in contact with semiconductor substrates; importantly, the structure and composition of these interfaces can influence both device functionality and the magnetic properties. Nanoscale ferromagnet/semiconductor structures are of particular interest. In this study, the interface structure between a monolayer of ferromagnetic magnetite (Fe3O4) nanoparticles and a GaAs substrate was studied using cross-sectional transmission electron microscopy techniques. It was found that a continuous amorphous oxide interface layer separates the nanoparticles from the GaAs substrate, and that iron diffused into the interface layer forming a compositional gradient. Electron energy-loss near-edge fine structures of the O K absorption edge revealed that the amorphous oxide is composed of γ-Fe2O3 directly underneath the Fe3O 4 nanoparticles, followed by a solid solution of Ga2O 3 and FeO and mostly Ga2O3 when approaching the buckled oxide/substrate interface. Real-space density functional theory calculations of the dynamical form factor confirmed the experimental observations. The implication of the findings on the optimization of these structures for spin injection is discussed.

UR - http://www.scopus.com/inward/record.url?scp=84906861062&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84906861062&partnerID=8YFLogxK

U2 - 10.1063/1.4893958

DO - 10.1063/1.4893958

M3 - Article

AN - SCOPUS:84906861062

VL - 116

JO - Journal of Applied Physics

JF - Journal of Applied Physics

SN - 0021-8979

IS - 8

M1 - 084306

ER -